diff --git a/weed/command/benchmark.go b/weed/command/benchmark.go
index 9adcb6f33..c83db02b4 100644
--- a/weed/command/benchmark.go
+++ b/weed/command/benchmark.go
@@ -127,7 +127,7 @@ func runBenchmark(cmd *Command, args []string) bool {
 		defer pprof.StopCPUProfile()
 	}
 
-	b.masterClient = wdclient.NewMasterClient(context.Background(), b.grpcDialOption, "client", strings.Split(*b.masters, ","))
+	b.masterClient = wdclient.NewMasterClient(b.grpcDialOption, "client", strings.Split(*b.masters, ","))
 	go b.masterClient.KeepConnectedToMaster()
 	b.masterClient.WaitUntilConnected()
 
@@ -314,8 +314,8 @@ func readFiles(fileIdLineChan chan string, s *stat) {
 }
 
 func grpcFileGet(volumeServer, fid string, grpcDialOption grpc.DialOption) (bytesRead int, err error) {
-	err = operation.WithVolumeServerClient(volumeServer, grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
-		fileGetClient, err := client.FileGet(ctx, &volume_server_pb.FileGetRequest{FileId: fid})
+	err = operation.WithVolumeServerClient(volumeServer, grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
+		fileGetClient, err := client.FileGet(context.Background(), &volume_server_pb.FileGetRequest{FileId: fid})
 		if err != nil {
 			return err
 		}
diff --git a/weed/command/filer_copy.go b/weed/command/filer_copy.go
index 6470cbbca..2edceb715 100644
--- a/weed/command/filer_copy.go
+++ b/weed/command/filer_copy.go
@@ -161,7 +161,7 @@ func runCopy(cmd *Command, args []string) bool {
 }
 
 func readFilerConfiguration(ctx context.Context, grpcDialOption grpc.DialOption, filerGrpcAddress string) (masters []string, collection, replication string, maxMB uint32, err error) {
-	err = withFilerClient(ctx, filerGrpcAddress, grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
+	err = withFilerClient(filerGrpcAddress, grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 		resp, err := client.GetFilerConfiguration(ctx, &filer_pb.GetFilerConfigurationRequest{})
 		if err != nil {
 			return fmt.Errorf("get filer %s configuration: %v", filerGrpcAddress, err)
@@ -257,13 +257,13 @@ func (worker *FileCopyWorker) doEachCopy(ctx context.Context, task FileCopyTask)
 	}
 
 	if chunkCount == 1 {
-		return worker.uploadFileAsOne(ctx, task, f)
+		return worker.uploadFileAsOne(task, f)
 	}
 
-	return worker.uploadFileInChunks(ctx, task, f, chunkCount, chunkSize)
+	return worker.uploadFileInChunks(task, f, chunkCount, chunkSize)
 }
 
-func (worker *FileCopyWorker) uploadFileAsOne(ctx context.Context, task FileCopyTask, f *os.File) error {
+func (worker *FileCopyWorker) uploadFileAsOne(task FileCopyTask, f *os.File) error {
 
 	// upload the file content
 	fileName := filepath.Base(f.Name())
@@ -276,7 +276,7 @@ func (worker *FileCopyWorker) uploadFileAsOne(ctx context.Context, task FileCopy
 	if task.fileSize > 0 {
 
 		// assign a volume
-		err := withFilerClient(ctx, worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
+		err := withFilerClient(worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 
 			request := &filer_pb.AssignVolumeRequest{
 				Count:       1,
@@ -286,7 +286,7 @@ func (worker *FileCopyWorker) uploadFileAsOne(ctx context.Context, task FileCopy
 				ParentPath:  task.destinationUrlPath,
 			}
 
-			assignResult, assignError = client.AssignVolume(ctx, request)
+			assignResult, assignError = client.AssignVolume(context.Background(), request)
 			if assignError != nil {
 				return fmt.Errorf("assign volume failure %v: %v", request, assignError)
 			}
@@ -321,7 +321,7 @@ func (worker *FileCopyWorker) uploadFileAsOne(ctx context.Context, task FileCopy
 		fmt.Printf("copied %s => http://%s%s%s\n", fileName, worker.filerHost, task.destinationUrlPath, fileName)
 	}
 
-	if err := withFilerClient(ctx, worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
+	if err := withFilerClient(worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 		request := &filer_pb.CreateEntryRequest{
 			Directory: task.destinationUrlPath,
 			Entry: &filer_pb.Entry{
@@ -342,7 +342,7 @@ func (worker *FileCopyWorker) uploadFileAsOne(ctx context.Context, task FileCopy
 			},
 		}
 
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			return fmt.Errorf("update fh: %v", err)
 		}
 		return nil
@@ -353,7 +353,7 @@ func (worker *FileCopyWorker) uploadFileAsOne(ctx context.Context, task FileCopy
 	return nil
 }
 
-func (worker *FileCopyWorker) uploadFileInChunks(ctx context.Context, task FileCopyTask, f *os.File, chunkCount int, chunkSize int64) error {
+func (worker *FileCopyWorker) uploadFileInChunks(task FileCopyTask, f *os.File, chunkCount int, chunkSize int64) error {
 
 	fileName := filepath.Base(f.Name())
 	mimeType := detectMimeType(f)
@@ -377,7 +377,7 @@ func (worker *FileCopyWorker) uploadFileInChunks(ctx context.Context, task FileC
 			// assign a volume
 			var assignResult *filer_pb.AssignVolumeResponse
 			var assignError error
-			err := withFilerClient(ctx, worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
+			err := withFilerClient(worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 				request := &filer_pb.AssignVolumeRequest{
 					Count:       1,
 					Replication: *worker.options.replication,
@@ -386,7 +386,7 @@ func (worker *FileCopyWorker) uploadFileInChunks(ctx context.Context, task FileC
 					ParentPath:  task.destinationUrlPath,
 				}
 
-				assignResult, assignError = client.AssignVolume(ctx, request)
+				assignResult, assignError = client.AssignVolume(context.Background(), request)
 				if assignError != nil {
 					return fmt.Errorf("assign volume failure %v: %v", request, assignError)
 				}
@@ -449,7 +449,7 @@ func (worker *FileCopyWorker) uploadFileInChunks(ctx context.Context, task FileC
 		return uploadError
 	}
 
-	if err := withFilerClient(ctx, worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
+	if err := withFilerClient(worker.filerGrpcAddress, worker.options.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 		request := &filer_pb.CreateEntryRequest{
 			Directory: task.destinationUrlPath,
 			Entry: &filer_pb.Entry{
@@ -470,7 +470,7 @@ func (worker *FileCopyWorker) uploadFileInChunks(ctx context.Context, task FileC
 			},
 		}
 
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			return fmt.Errorf("update fh: %v", err)
 		}
 		return nil
@@ -499,9 +499,9 @@ func detectMimeType(f *os.File) string {
 	return mimeType
 }
 
-func withFilerClient(ctx context.Context, filerAddress string, grpcDialOption grpc.DialOption, fn func(filer_pb.SeaweedFilerClient) error) error {
+func withFilerClient(filerAddress string, grpcDialOption grpc.DialOption, fn func(filer_pb.SeaweedFilerClient) error) error {
 
-	return util.WithCachedGrpcClient(ctx, func(ctx context.Context, clientConn *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(clientConn *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(clientConn)
 		return fn(client)
 	}, filerAddress, grpcDialOption)
diff --git a/weed/command/s3.go b/weed/command/s3.go
index 0eff76d32..abd32e545 100644
--- a/weed/command/s3.go
+++ b/weed/command/s3.go
@@ -128,7 +128,7 @@ func (s3opt *S3Options) startS3Server() bool {
 	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.client")
 	ctx := context.Background()
 
-	err = withFilerClient(ctx, filerGrpcAddress, grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
+	err = withFilerClient(filerGrpcAddress, grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 		resp, err := client.GetFilerConfiguration(ctx, &filer_pb.GetFilerConfigurationRequest{})
 		if err != nil {
 			return fmt.Errorf("get filer %s configuration: %v", filerGrpcAddress, err)
diff --git a/weed/filer2/filer.go b/weed/filer2/filer.go
index b84a67b22..181a250f2 100644
--- a/weed/filer2/filer.go
+++ b/weed/filer2/filer.go
@@ -37,7 +37,7 @@ type Filer struct {
 func NewFiler(masters []string, grpcDialOption grpc.DialOption, bucketFolder string) *Filer {
 	f := &Filer{
 		directoryCache:      ccache.New(ccache.Configure().MaxSize(1000).ItemsToPrune(100)),
-		MasterClient:        wdclient.NewMasterClient(context.Background(), grpcDialOption, "filer", masters),
+		MasterClient:        wdclient.NewMasterClient(grpcDialOption, "filer", masters),
 		fileIdDeletionQueue: util.NewUnboundedQueue(),
 		GrpcDialOption:      grpcDialOption,
 	}
diff --git a/weed/filer2/filer_client_util.go b/weed/filer2/filer_client_util.go
index af804b909..9e03d60c4 100644
--- a/weed/filer2/filer_client_util.go
+++ b/weed/filer2/filer_client_util.go
@@ -22,10 +22,10 @@ func VolumeId(fileId string) string {
 }
 
 type FilerClient interface {
-	WithFilerClient(ctx context.Context, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error
+	WithFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error
 }
 
-func ReadIntoBuffer(ctx context.Context, filerClient FilerClient, fullFilePath FullPath, buff []byte, chunkViews []*ChunkView, baseOffset int64) (totalRead int64, err error) {
+func ReadIntoBuffer(filerClient FilerClient, fullFilePath FullPath, buff []byte, chunkViews []*ChunkView, baseOffset int64) (totalRead int64, err error) {
 	var vids []string
 	for _, chunkView := range chunkViews {
 		vids = append(vids, VolumeId(chunkView.FileId))
@@ -33,10 +33,10 @@ func ReadIntoBuffer(ctx context.Context, filerClient FilerClient, fullFilePath F
 
 	vid2Locations := make(map[string]*filer_pb.Locations)
 
-	err = filerClient.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = filerClient.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		glog.V(4).Infof("read fh lookup volume id locations: %v", vids)
-		resp, err := client.LookupVolume(ctx, &filer_pb.LookupVolumeRequest{
+		resp, err := client.LookupVolume(context.Background(), &filer_pb.LookupVolumeRequest{
 			VolumeIds: vids,
 		})
 		if err != nil {
@@ -93,11 +93,11 @@ func ReadIntoBuffer(ctx context.Context, filerClient FilerClient, fullFilePath F
 	return
 }
 
-func GetEntry(ctx context.Context, filerClient FilerClient, fullFilePath FullPath) (entry *filer_pb.Entry, err error) {
+func GetEntry(filerClient FilerClient, fullFilePath FullPath) (entry *filer_pb.Entry, err error) {
 
 	dir, name := fullFilePath.DirAndName()
 
-	err = filerClient.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = filerClient.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Directory: dir,
@@ -105,7 +105,7 @@ func GetEntry(ctx context.Context, filerClient FilerClient, fullFilePath FullPat
 		}
 
 		// glog.V(3).Infof("read %s request: %v", fullFilePath, request)
-		resp, err := client.LookupDirectoryEntry(ctx, request)
+		resp, err := client.LookupDirectoryEntry(context.Background(), request)
 		if err != nil {
 			if err == ErrNotFound || strings.Contains(err.Error(), ErrNotFound.Error()) {
 				return nil
@@ -126,9 +126,9 @@ func GetEntry(ctx context.Context, filerClient FilerClient, fullFilePath FullPat
 	return
 }
 
-func ReadDirAllEntries(ctx context.Context, filerClient FilerClient, fullDirPath FullPath, prefix string, fn func(entry *filer_pb.Entry, isLast bool)) (err error) {
+func ReadDirAllEntries(filerClient FilerClient, fullDirPath FullPath, prefix string, fn func(entry *filer_pb.Entry, isLast bool)) (err error) {
 
-	err = filerClient.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = filerClient.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		lastEntryName := ""
 
@@ -140,7 +140,7 @@ func ReadDirAllEntries(ctx context.Context, filerClient FilerClient, fullDirPath
 		}
 
 		glog.V(3).Infof("read directory: %v", request)
-		stream, err := client.ListEntries(ctx, request)
+		stream, err := client.ListEntries(context.Background(), request)
 		if err != nil {
 			return fmt.Errorf("list %s: %v", fullDirPath, err)
 		}
diff --git a/weed/filer2/filer_delete_entry.go b/weed/filer2/filer_delete_entry.go
index af88d1512..d0792ac66 100644
--- a/weed/filer2/filer_delete_entry.go
+++ b/weed/filer2/filer_delete_entry.go
@@ -45,7 +45,7 @@ func (f *Filer) DeleteEntryMetaAndData(ctx context.Context, p FullPath, isRecurs
 	}
 	if isCollection {
 		collectionName := entry.Name()
-		f.doDeleteCollection(ctx, collectionName)
+		f.doDeleteCollection(collectionName)
 		f.deleteBucket(collectionName)
 	}
 
@@ -110,10 +110,10 @@ func (f *Filer) doDeleteEntryMetaAndData(ctx context.Context, entry *Entry, shou
 	return nil
 }
 
-func (f *Filer) doDeleteCollection(ctx context.Context, collectionName string) (err error) {
+func (f *Filer) doDeleteCollection(collectionName string) (err error) {
 
-	return f.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		_, err := client.CollectionDelete(ctx, &master_pb.CollectionDeleteRequest{
+	return f.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		_, err := client.CollectionDelete(context.Background(), &master_pb.CollectionDeleteRequest{
 			Name: collectionName,
 		})
 		if err != nil {
diff --git a/weed/filesys/dir.go b/weed/filesys/dir.go
index 2a4f6fa75..c897ed827 100644
--- a/weed/filesys/dir.go
+++ b/weed/filesys/dir.go
@@ -126,10 +126,10 @@ func (dir *Dir) Create(ctx context.Context, req *fuse.CreateRequest,
 		},
 		OExcl: req.Flags&fuse.OpenExclusive != 0,
 	}
-	glog.V(1).Infof("create: %v", req.String())
+	glog.V(1).Infof("create %s/%s: %v", dir.Path, req.Name, req.Flags)
 
-	if err := dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+	if err := dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			if strings.Contains(err.Error(), "EEXIST") {
 				return fuse.EEXIST
 			}
@@ -167,7 +167,7 @@ func (dir *Dir) Mkdir(ctx context.Context, req *fuse.MkdirRequest) (fs.Node, err
 		},
 	}
 
-	err := dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err := dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.CreateEntryRequest{
 			Directory: dir.Path,
@@ -175,7 +175,7 @@ func (dir *Dir) Mkdir(ctx context.Context, req *fuse.MkdirRequest) (fs.Node, err
 		}
 
 		glog.V(1).Infof("mkdir: %v", request)
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			glog.V(0).Infof("mkdir %s/%s: %v", dir.Path, req.Name, err)
 			return err
 		}
@@ -200,7 +200,7 @@ func (dir *Dir) Lookup(ctx context.Context, req *fuse.LookupRequest, resp *fuse.
 
 	if entry == nil {
 		// glog.V(3).Infof("dir Lookup cache miss %s", fullFilePath)
-		entry, err = filer2.GetEntry(ctx, dir.wfs, fullFilePath)
+		entry, err = filer2.GetEntry(dir.wfs, fullFilePath)
 		if err != nil {
 			glog.V(1).Infof("dir GetEntry %s: %v", fullFilePath, err)
 			return nil, fuse.ENOENT
@@ -239,7 +239,7 @@ func (dir *Dir) ReadDirAll(ctx context.Context) (ret []fuse.Dirent, err error) {
 
 	cacheTtl := 5 * time.Minute
 
-	readErr := filer2.ReadDirAllEntries(ctx, dir.wfs, filer2.FullPath(dir.Path), "", func(entry *filer_pb.Entry, isLast bool) {
+	readErr := filer2.ReadDirAllEntries(dir.wfs, filer2.FullPath(dir.Path), "", func(entry *filer_pb.Entry, isLast bool) {
 		fullpath := filer2.NewFullPath(dir.Path, entry.Name)
 		inode := fullpath.AsInode()
 		if entry.IsDirectory {
@@ -262,17 +262,17 @@ func (dir *Dir) ReadDirAll(ctx context.Context) (ret []fuse.Dirent, err error) {
 func (dir *Dir) Remove(ctx context.Context, req *fuse.RemoveRequest) error {
 
 	if !req.Dir {
-		return dir.removeOneFile(ctx, req)
+		return dir.removeOneFile(req)
 	}
 
-	return dir.removeFolder(ctx, req)
+	return dir.removeFolder(req)
 
 }
 
-func (dir *Dir) removeOneFile(ctx context.Context, req *fuse.RemoveRequest) error {
+func (dir *Dir) removeOneFile(req *fuse.RemoveRequest) error {
 
 	filePath := filer2.NewFullPath(dir.Path, req.Name)
-	entry, err := filer2.GetEntry(ctx, dir.wfs, filePath)
+	entry, err := filer2.GetEntry(dir.wfs, filePath)
 	if err != nil {
 		return err
 	}
@@ -280,11 +280,11 @@ func (dir *Dir) removeOneFile(ctx context.Context, req *fuse.RemoveRequest) erro
 		return nil
 	}
 
-	dir.wfs.deleteFileChunks(ctx, entry.Chunks)
+	dir.wfs.deleteFileChunks(entry.Chunks)
 
 	dir.wfs.cacheDelete(filePath)
 
-	return dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.DeleteEntryRequest{
 			Directory:    dir.Path,
@@ -293,7 +293,7 @@ func (dir *Dir) removeOneFile(ctx context.Context, req *fuse.RemoveRequest) erro
 		}
 
 		glog.V(3).Infof("remove file: %v", request)
-		_, err := client.DeleteEntry(ctx, request)
+		_, err := client.DeleteEntry(context.Background(), request)
 		if err != nil {
 			glog.V(3).Infof("not found remove file %s/%s: %v", dir.Path, req.Name, err)
 			return fuse.ENOENT
@@ -304,11 +304,11 @@ func (dir *Dir) removeOneFile(ctx context.Context, req *fuse.RemoveRequest) erro
 
 }
 
-func (dir *Dir) removeFolder(ctx context.Context, req *fuse.RemoveRequest) error {
+func (dir *Dir) removeFolder(req *fuse.RemoveRequest) error {
 
 	dir.wfs.cacheDelete(filer2.NewFullPath(dir.Path, req.Name))
 
-	return dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.DeleteEntryRequest{
 			Directory:    dir.Path,
@@ -317,7 +317,7 @@ func (dir *Dir) removeFolder(ctx context.Context, req *fuse.RemoveRequest) error
 		}
 
 		glog.V(3).Infof("remove directory entry: %v", request)
-		_, err := client.DeleteEntry(ctx, request)
+		_, err := client.DeleteEntry(context.Background(), request)
 		if err != nil {
 			glog.V(3).Infof("not found remove %s/%s: %v", dir.Path, req.Name, err)
 			return fuse.ENOENT
@@ -419,7 +419,7 @@ func (dir *Dir) Forget() {
 func (dir *Dir) maybeLoadEntry(ctx context.Context) error {
 	if dir.entry == nil {
 		parentDirPath, name := filer2.FullPath(dir.Path).DirAndName()
-		entry, err := dir.wfs.maybeLoadEntry(ctx, parentDirPath, name)
+		entry, err := dir.wfs.maybeLoadEntry(parentDirPath, name)
 		if err != nil {
 			return err
 		}
@@ -432,7 +432,7 @@ func (dir *Dir) saveEntry(ctx context.Context) error {
 
 	parentDir, name := filer2.FullPath(dir.Path).DirAndName()
 
-	return dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.UpdateEntryRequest{
 			Directory: parentDir,
@@ -440,7 +440,7 @@ func (dir *Dir) saveEntry(ctx context.Context) error {
 		}
 
 		glog.V(1).Infof("save dir entry: %v", request)
-		_, err := client.UpdateEntry(ctx, request)
+		_, err := client.UpdateEntry(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("UpdateEntry dir %s/%s: %v", parentDir, name, err)
 			return fuse.EIO
diff --git a/weed/filesys/dir_link.go b/weed/filesys/dir_link.go
index 8b7ec7e89..61ed04c26 100644
--- a/weed/filesys/dir_link.go
+++ b/weed/filesys/dir_link.go
@@ -35,8 +35,8 @@ func (dir *Dir) Symlink(ctx context.Context, req *fuse.SymlinkRequest) (fs.Node,
 		},
 	}
 
-	err := dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+	err := dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			glog.V(0).Infof("symlink %s/%s: %v", dir.Path, req.NewName, err)
 			return fuse.EIO
 		}
diff --git a/weed/filesys/dir_rename.go b/weed/filesys/dir_rename.go
index 4eb3c15b5..9b0c0fe6e 100644
--- a/weed/filesys/dir_rename.go
+++ b/weed/filesys/dir_rename.go
@@ -15,7 +15,7 @@ func (dir *Dir) Rename(ctx context.Context, req *fuse.RenameRequest, newDirector
 	newDir := newDirectory.(*Dir)
 	glog.V(4).Infof("dir Rename %s/%s => %s/%s", dir.Path, req.OldName, newDir.Path, req.NewName)
 
-	err := dir.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err := dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.AtomicRenameEntryRequest{
 			OldDirectory: dir.Path,
@@ -24,7 +24,7 @@ func (dir *Dir) Rename(ctx context.Context, req *fuse.RenameRequest, newDirector
 			NewName:      req.NewName,
 		}
 
-		_, err := client.AtomicRenameEntry(ctx, request)
+		_, err := client.AtomicRenameEntry(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("dir Rename %s/%s => %s/%s : %v", dir.Path, req.OldName, newDir.Path, req.NewName, err)
 			return fuse.EIO
diff --git a/weed/filesys/dirty_page.go b/weed/filesys/dirty_page.go
index 659f33736..3fbc7dca7 100644
--- a/weed/filesys/dirty_page.go
+++ b/weed/filesys/dirty_page.go
@@ -52,7 +52,7 @@ func (pages *ContinuousDirtyPages) AddPage(ctx context.Context, offset int64, da
 	var hasSavedData bool
 
 	if pages.intervals.TotalSize() > pages.f.wfs.option.ChunkSizeLimit {
-		chunk, hasSavedData, err = pages.saveExistingLargestPageToStorage(ctx)
+		chunk, hasSavedData, err = pages.saveExistingLargestPageToStorage()
 		if hasSavedData {
 			chunks = append(chunks, chunk)
 		}
@@ -67,7 +67,7 @@ func (pages *ContinuousDirtyPages) flushAndSave(ctx context.Context, offset int6
 	var newChunks []*filer_pb.FileChunk
 
 	// flush existing
-	if newChunks, err = pages.saveExistingPagesToStorage(ctx); err == nil {
+	if newChunks, err = pages.saveExistingPagesToStorage(); err == nil {
 		if newChunks != nil {
 			chunks = append(chunks, newChunks...)
 		}
@@ -76,7 +76,7 @@ func (pages *ContinuousDirtyPages) flushAndSave(ctx context.Context, offset int6
 	}
 
 	// flush the new page
-	if chunk, err = pages.saveToStorage(ctx, bytes.NewReader(data), offset, int64(len(data))); err == nil {
+	if chunk, err = pages.saveToStorage(bytes.NewReader(data), offset, int64(len(data))); err == nil {
 		if chunk != nil {
 			glog.V(4).Infof("%s/%s flush big request [%d,%d) to %s", pages.f.dir.Path, pages.f.Name, chunk.Offset, chunk.Offset+int64(chunk.Size), chunk.FileId)
 			chunks = append(chunks, chunk)
@@ -89,22 +89,22 @@ func (pages *ContinuousDirtyPages) flushAndSave(ctx context.Context, offset int6
 	return
 }
 
-func (pages *ContinuousDirtyPages) FlushToStorage(ctx context.Context) (chunks []*filer_pb.FileChunk, err error) {
+func (pages *ContinuousDirtyPages) FlushToStorage() (chunks []*filer_pb.FileChunk, err error) {
 
 	pages.lock.Lock()
 	defer pages.lock.Unlock()
 
-	return pages.saveExistingPagesToStorage(ctx)
+	return pages.saveExistingPagesToStorage()
 }
 
-func (pages *ContinuousDirtyPages) saveExistingPagesToStorage(ctx context.Context) (chunks []*filer_pb.FileChunk, err error) {
+func (pages *ContinuousDirtyPages) saveExistingPagesToStorage() (chunks []*filer_pb.FileChunk, err error) {
 
 	var hasSavedData bool
 	var chunk *filer_pb.FileChunk
 
 	for {
 
-		chunk, hasSavedData, err = pages.saveExistingLargestPageToStorage(ctx)
+		chunk, hasSavedData, err = pages.saveExistingLargestPageToStorage()
 		if !hasSavedData {
 			return chunks, err
 		}
@@ -118,14 +118,14 @@ func (pages *ContinuousDirtyPages) saveExistingPagesToStorage(ctx context.Contex
 
 }
 
-func (pages *ContinuousDirtyPages) saveExistingLargestPageToStorage(ctx context.Context) (chunk *filer_pb.FileChunk, hasSavedData bool, err error) {
+func (pages *ContinuousDirtyPages) saveExistingLargestPageToStorage() (chunk *filer_pb.FileChunk, hasSavedData bool, err error) {
 
 	maxList := pages.intervals.RemoveLargestIntervalLinkedList()
 	if maxList == nil {
 		return nil, false, nil
 	}
 
-	chunk, err = pages.saveToStorage(ctx, maxList.ToReader(), maxList.Offset(), maxList.Size())
+	chunk, err = pages.saveToStorage(maxList.ToReader(), maxList.Offset(), maxList.Size())
 	if err == nil {
 		hasSavedData = true
 		glog.V(3).Infof("%s saveToStorage [%d,%d) %s", pages.f.fullpath(), maxList.Offset(), maxList.Offset()+maxList.Size(), chunk.FileId)
@@ -137,14 +137,14 @@ func (pages *ContinuousDirtyPages) saveExistingLargestPageToStorage(ctx context.
 	return
 }
 
-func (pages *ContinuousDirtyPages) saveToStorage(ctx context.Context, reader io.Reader, offset int64, size int64) (*filer_pb.FileChunk, error) {
+func (pages *ContinuousDirtyPages) saveToStorage(reader io.Reader, offset int64, size int64) (*filer_pb.FileChunk, error) {
 
 	var fileId, host string
 	var auth security.EncodedJwt
 
 	dir, _ := pages.f.fullpath().DirAndName()
 
-	if err := pages.f.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	if err := pages.f.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.AssignVolumeRequest{
 			Count:       1,
@@ -155,7 +155,7 @@ func (pages *ContinuousDirtyPages) saveToStorage(ctx context.Context, reader io.
 			ParentPath:  dir,
 		}
 
-		resp, err := client.AssignVolume(ctx, request)
+		resp, err := client.AssignVolume(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("assign volume failure %v: %v", request, err)
 			return err
diff --git a/weed/filesys/file.go b/weed/filesys/file.go
index eccef4e58..69d440a73 100644
--- a/weed/filesys/file.go
+++ b/weed/filesys/file.go
@@ -148,7 +148,7 @@ func (file *File) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *f
 
 	file.wfs.cacheDelete(file.fullpath())
 
-	return file.saveEntry(ctx)
+	return file.saveEntry()
 
 }
 
@@ -166,7 +166,7 @@ func (file *File) Setxattr(ctx context.Context, req *fuse.SetxattrRequest) error
 
 	file.wfs.cacheDelete(file.fullpath())
 
-	return file.saveEntry(ctx)
+	return file.saveEntry()
 
 }
 
@@ -184,7 +184,7 @@ func (file *File) Removexattr(ctx context.Context, req *fuse.RemovexattrRequest)
 
 	file.wfs.cacheDelete(file.fullpath())
 
-	return file.saveEntry(ctx)
+	return file.saveEntry()
 
 }
 
@@ -221,7 +221,7 @@ func (file *File) Forget() {
 
 func (file *File) maybeLoadEntry(ctx context.Context) error {
 	if file.entry == nil || file.isOpen <= 0 {
-		entry, err := file.wfs.maybeLoadEntry(ctx, file.dir.Path, file.Name)
+		entry, err := file.wfs.maybeLoadEntry(file.dir.Path, file.Name)
 		if err != nil {
 			return err
 		}
@@ -256,8 +256,8 @@ func (file *File) setEntry(entry *filer_pb.Entry) {
 	file.entryViewCache = filer2.NonOverlappingVisibleIntervals(file.entry.Chunks)
 }
 
-func (file *File) saveEntry(ctx context.Context) error {
-	return file.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+func (file *File) saveEntry() error {
+	return file.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.UpdateEntryRequest{
 			Directory: file.dir.Path,
@@ -265,7 +265,7 @@ func (file *File) saveEntry(ctx context.Context) error {
 		}
 
 		glog.V(1).Infof("save file entry: %v", request)
-		_, err := client.UpdateEntry(ctx, request)
+		_, err := client.UpdateEntry(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("UpdateEntry file %s/%s: %v", file.dir.Path, file.Name, err)
 			return fuse.EIO
diff --git a/weed/filesys/filehandle.go b/weed/filesys/filehandle.go
index 71954d75d..7b26c5952 100644
--- a/weed/filesys/filehandle.go
+++ b/weed/filesys/filehandle.go
@@ -89,7 +89,7 @@ func (fh *FileHandle) readFromChunks(ctx context.Context, buff []byte, offset in
 
 	chunkViews := filer2.ViewFromVisibleIntervals(fh.f.entryViewCache, offset, len(buff))
 
-	totalRead, err := filer2.ReadIntoBuffer(ctx, fh.f.wfs, fh.f.fullpath(), buff, chunkViews, offset)
+	totalRead, err := filer2.ReadIntoBuffer(fh.f.wfs, fh.f.fullpath(), buff, chunkViews, offset)
 
 	if err != nil {
 		glog.Errorf("file handle read %s: %v", fh.f.fullpath(), err)
@@ -154,7 +154,7 @@ func (fh *FileHandle) Flush(ctx context.Context, req *fuse.FlushRequest) error {
 	// send the data to the OS
 	glog.V(4).Infof("%s fh %d flush %v", fh.f.fullpath(), fh.handle, req)
 
-	chunks, err := fh.dirtyPages.FlushToStorage(ctx)
+	chunks, err := fh.dirtyPages.FlushToStorage()
 	if err != nil {
 		glog.Errorf("flush %s: %v", fh.f.fullpath(), err)
 		return fuse.EIO
@@ -169,7 +169,7 @@ func (fh *FileHandle) Flush(ctx context.Context, req *fuse.FlushRequest) error {
 		return nil
 	}
 
-	err = fh.f.wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = fh.f.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		if fh.f.entry.Attributes != nil {
 			fh.f.entry.Attributes.Mime = fh.contentType
@@ -196,12 +196,12 @@ func (fh *FileHandle) Flush(ctx context.Context, req *fuse.FlushRequest) error {
 		fh.f.entry.Chunks = chunks
 		// fh.f.entryViewCache = nil
 
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
-			glog.Errorf("update fh: %v", err)
-			return fmt.Errorf("update fh: %v", err)
+		if err := filer_pb.CreateEntry(client, request); err != nil {
+			glog.Errorf("fh flush create %s: %v", fh.f.fullpath(), err)
+			return fmt.Errorf("fh flush create %s: %v", fh.f.fullpath(), err)
 		}
 
-		fh.f.wfs.deleteFileChunks(ctx, garbages)
+		fh.f.wfs.deleteFileChunks(garbages)
 		for i, chunk := range garbages {
 			glog.V(3).Infof("garbage %s chunks %d: %v [%d,%d)", fh.f.fullpath(), i, chunk.FileId, chunk.Offset, chunk.Offset+int64(chunk.Size))
 		}
diff --git a/weed/filesys/wfs.go b/weed/filesys/wfs.go
index 37bb92acc..8f4225fb0 100644
--- a/weed/filesys/wfs.go
+++ b/weed/filesys/wfs.go
@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"math"
 	"os"
-	"strings"
 	"sync"
 	"time"
 
@@ -88,23 +87,16 @@ func (wfs *WFS) Root() (fs.Node, error) {
 	return wfs.root, nil
 }
 
-func (wfs *WFS) WithFilerClient(ctx context.Context, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error {
+func (wfs *WFS) WithFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
 
-	err := util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	err := util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, wfs.option.FilerGrpcAddress, wfs.option.GrpcDialOption)
 
 	if err == nil {
 		return nil
 	}
-	if strings.Contains(err.Error(), "context canceled") {
-		glog.V(0).Infoln("retry context canceled request...")
-		return util.WithCachedGrpcClient(context.Background(), func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
-			client := filer_pb.NewSeaweedFilerClient(grpcConnection)
-			return fn(ctx2, client)
-		}, wfs.option.FilerGrpcAddress, wfs.option.GrpcDialOption)
-	}
 	return err
 
 }
@@ -162,7 +154,7 @@ func (wfs *WFS) Statfs(ctx context.Context, req *fuse.StatfsRequest, resp *fuse.
 
 	if wfs.stats.lastChecked < time.Now().Unix()-20 {
 
-		err := wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+		err := wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 			request := &filer_pb.StatisticsRequest{
 				Collection:  wfs.option.Collection,
@@ -171,7 +163,7 @@ func (wfs *WFS) Statfs(ctx context.Context, req *fuse.StatfsRequest, resp *fuse.
 			}
 
 			glog.V(4).Infof("reading filer stats: %+v", request)
-			resp, err := client.Statistics(ctx, request)
+			resp, err := client.Statistics(context.Background(), request)
 			if err != nil {
 				glog.V(0).Infof("reading filer stats %v: %v", request, err)
 				return err
diff --git a/weed/filesys/wfs_deletion.go b/weed/filesys/wfs_deletion.go
index cce0c792c..f53e95d26 100644
--- a/weed/filesys/wfs_deletion.go
+++ b/weed/filesys/wfs_deletion.go
@@ -10,7 +10,7 @@ import (
 	"google.golang.org/grpc"
 )
 
-func (wfs *WFS) deleteFileChunks(ctx context.Context, chunks []*filer_pb.FileChunk) {
+func (wfs *WFS) deleteFileChunks(chunks []*filer_pb.FileChunk) {
 	if len(chunks) == 0 {
 		return
 	}
@@ -20,13 +20,13 @@ func (wfs *WFS) deleteFileChunks(ctx context.Context, chunks []*filer_pb.FileChu
 		fileIds = append(fileIds, chunk.GetFileIdString())
 	}
 
-	wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-		deleteFileIds(ctx, wfs.option.GrpcDialOption, client, fileIds)
+	wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+		deleteFileIds(wfs.option.GrpcDialOption, client, fileIds)
 		return nil
 	})
 }
 
-func deleteFileIds(ctx context.Context, grpcDialOption grpc.DialOption, client filer_pb.SeaweedFilerClient, fileIds []string) error {
+func deleteFileIds(grpcDialOption grpc.DialOption, client filer_pb.SeaweedFilerClient, fileIds []string) error {
 
 	var vids []string
 	for _, fileId := range fileIds {
@@ -38,7 +38,7 @@ func deleteFileIds(ctx context.Context, grpcDialOption grpc.DialOption, client f
 		m := make(map[string]operation.LookupResult)
 
 		glog.V(4).Infof("remove file lookup volume id locations: %v", vids)
-		resp, err := client.LookupVolume(ctx, &filer_pb.LookupVolumeRequest{
+		resp, err := client.LookupVolume(context.Background(), &filer_pb.LookupVolumeRequest{
 			VolumeIds: vids,
 		})
 		if err != nil {
diff --git a/weed/filesys/xattr.go b/weed/filesys/xattr.go
index 9dfb491fd..3ccecdf98 100644
--- a/weed/filesys/xattr.go
+++ b/weed/filesys/xattr.go
@@ -108,7 +108,7 @@ func listxattr(entry *filer_pb.Entry, req *fuse.ListxattrRequest, resp *fuse.Lis
 
 }
 
-func (wfs *WFS) maybeLoadEntry(ctx context.Context, dir, name string) (entry *filer_pb.Entry, err error) {
+func (wfs *WFS) maybeLoadEntry(dir, name string) (entry *filer_pb.Entry, err error) {
 
 	fullpath := filer2.NewFullPath(dir, name)
 	entry = wfs.cacheGet(fullpath)
@@ -117,14 +117,14 @@ func (wfs *WFS) maybeLoadEntry(ctx context.Context, dir, name string) (entry *fi
 	}
 	// glog.V(3).Infof("read entry cache miss %s", fullpath)
 
-	err = wfs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Name:      name,
 			Directory: dir,
 		}
 
-		resp, err := client.LookupDirectoryEntry(ctx, request)
+		resp, err := client.LookupDirectoryEntry(context.Background(), request)
 		if err != nil || resp == nil || resp.Entry == nil {
 			if err == filer2.ErrNotFound || strings.Contains(err.Error(), filer2.ErrNotFound.Error()) {
 				glog.V(3).Infof("file attr read not found file %v: %v", request, err)
diff --git a/weed/operation/assign_file_id.go b/weed/operation/assign_file_id.go
index 6da30605b..893bf516c 100644
--- a/weed/operation/assign_file_id.go
+++ b/weed/operation/assign_file_id.go
@@ -46,7 +46,7 @@ func Assign(server string, grpcDialOption grpc.DialOption, primaryRequest *Volum
 			continue
 		}
 
-		lastError = WithMasterServerClient(server, grpcDialOption, func(ctx context.Context, masterClient master_pb.SeaweedClient) error {
+		lastError = WithMasterServerClient(server, grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
 
 			req := &master_pb.AssignRequest{
 				Count:               primaryRequest.Count,
diff --git a/weed/operation/delete_content.go b/weed/operation/delete_content.go
index 95bbde9f9..361c09e7e 100644
--- a/weed/operation/delete_content.go
+++ b/weed/operation/delete_content.go
@@ -10,7 +10,6 @@ import (
 
 	"google.golang.org/grpc"
 
-	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
 )
 
@@ -109,15 +108,13 @@ func DeleteFilesWithLookupVolumeId(grpcDialOption grpc.DialOption, fileIds []str
 		ret = append(ret, result...)
 	}
 
-	glog.V(1).Infof("deleted %d items", len(ret))
-
 	return ret, err
 }
 
 // DeleteFilesAtOneVolumeServer deletes a list of files that is on one volume server via gRpc
 func DeleteFilesAtOneVolumeServer(volumeServer string, grpcDialOption grpc.DialOption, fileIds []string) (ret []*volume_server_pb.DeleteResult, err error) {
 
-	err = WithVolumeServerClient(volumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
+	err = WithVolumeServerClient(volumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
 
 		req := &volume_server_pb.BatchDeleteRequest{
 			FileIds: fileIds,
diff --git a/weed/operation/grpc_client.go b/weed/operation/grpc_client.go
index e7ee2d2ba..7eed66503 100644
--- a/weed/operation/grpc_client.go
+++ b/weed/operation/grpc_client.go
@@ -1,29 +1,28 @@
 package operation
 
 import (
-	"context"
 	"fmt"
+	"strconv"
+	"strings"
+
+	"google.golang.org/grpc"
+
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
 	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"google.golang.org/grpc"
-	"strconv"
-	"strings"
 )
 
-func WithVolumeServerClient(volumeServer string, grpcDialOption grpc.DialOption, fn func(context.Context, volume_server_pb.VolumeServerClient) error) error {
-
-	ctx := context.Background()
+func WithVolumeServerClient(volumeServer string, grpcDialOption grpc.DialOption, fn func(volume_server_pb.VolumeServerClient) error) error {
 
 	grpcAddress, err := toVolumeServerGrpcAddress(volumeServer)
 	if err != nil {
 		return err
 	}
 
-	return util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := volume_server_pb.NewVolumeServerClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, grpcAddress, grpcDialOption)
 
 }
@@ -38,18 +37,16 @@ func toVolumeServerGrpcAddress(volumeServer string) (grpcAddress string, err err
 	return fmt.Sprintf("%s:%d", volumeServer[0:sepIndex], port+10000), nil
 }
 
-func WithMasterServerClient(masterServer string, grpcDialOption grpc.DialOption, fn func(ctx2 context.Context, masterClient master_pb.SeaweedClient) error) error {
-
-	ctx := context.Background()
+func WithMasterServerClient(masterServer string, grpcDialOption grpc.DialOption, fn func(masterClient master_pb.SeaweedClient) error) error {
 
 	masterGrpcAddress, parseErr := util.ParseServerToGrpcAddress(masterServer)
 	if parseErr != nil {
 		return fmt.Errorf("failed to parse master grpc %v: %v", masterServer, parseErr)
 	}
 
-	return util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := master_pb.NewSeaweedClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, masterGrpcAddress, grpcDialOption)
 
 }
diff --git a/weed/operation/lookup.go b/weed/operation/lookup.go
index 78769ac5a..d0773e7fd 100644
--- a/weed/operation/lookup.go
+++ b/weed/operation/lookup.go
@@ -99,12 +99,12 @@ func LookupVolumeIds(server string, grpcDialOption grpc.DialOption, vids []strin
 
 	//only query unknown_vids
 
-	err := WithMasterServerClient(server, grpcDialOption, func(ctx context.Context, masterClient master_pb.SeaweedClient) error {
+	err := WithMasterServerClient(server, grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
 
 		req := &master_pb.LookupVolumeRequest{
 			VolumeIds: unknown_vids,
 		}
-		resp, grpcErr := masterClient.LookupVolume(ctx, req)
+		resp, grpcErr := masterClient.LookupVolume(context.Background(), req)
 		if grpcErr != nil {
 			return grpcErr
 		}
diff --git a/weed/operation/stats.go b/weed/operation/stats.go
index 3e6327f19..b69a33750 100644
--- a/weed/operation/stats.go
+++ b/weed/operation/stats.go
@@ -9,9 +9,9 @@ import (
 
 func Statistics(server string, grpcDialOption grpc.DialOption, req *master_pb.StatisticsRequest) (resp *master_pb.StatisticsResponse, err error) {
 
-	err = WithMasterServerClient(server, grpcDialOption, func(ctx context.Context, masterClient master_pb.SeaweedClient) error {
+	err = WithMasterServerClient(server, grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
 
-		grpcResponse, grpcErr := masterClient.Statistics(ctx, req)
+		grpcResponse, grpcErr := masterClient.Statistics(context.Background(), req)
 		if grpcErr != nil {
 			return grpcErr
 		}
diff --git a/weed/operation/sync_volume.go b/weed/operation/sync_volume.go
index 4b39ad544..5562f12ab 100644
--- a/weed/operation/sync_volume.go
+++ b/weed/operation/sync_volume.go
@@ -8,9 +8,9 @@ import (
 
 func GetVolumeSyncStatus(server string, grpcDialOption grpc.DialOption, vid uint32) (resp *volume_server_pb.VolumeSyncStatusResponse, err error) {
 
-	WithVolumeServerClient(server, grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	WithVolumeServerClient(server, grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
-		resp, err = client.VolumeSyncStatus(ctx, &volume_server_pb.VolumeSyncStatusRequest{
+		resp, err = client.VolumeSyncStatus(context.Background(), &volume_server_pb.VolumeSyncStatusRequest{
 			VolumeId: vid,
 		})
 		return nil
diff --git a/weed/operation/tail_volume.go b/weed/operation/tail_volume.go
index 1e8b0a16e..3cd66b5da 100644
--- a/weed/operation/tail_volume.go
+++ b/weed/operation/tail_volume.go
@@ -5,9 +5,10 @@ import (
 	"fmt"
 	"io"
 
+	"google.golang.org/grpc"
+
 	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
 	"github.com/chrislusf/seaweedfs/weed/storage/needle"
-	"google.golang.org/grpc"
 )
 
 func TailVolume(master string, grpcDialOption grpc.DialOption, vid needle.VolumeId, sinceNs uint64, timeoutSeconds int, fn func(n *needle.Needle) error) error {
@@ -26,9 +27,9 @@ func TailVolume(master string, grpcDialOption grpc.DialOption, vid needle.Volume
 }
 
 func TailVolumeFromSource(volumeServer string, grpcDialOption grpc.DialOption, vid needle.VolumeId, sinceNs uint64, idleTimeoutSeconds int, fn func(n *needle.Needle) error) error {
-	return WithVolumeServerClient(volumeServer, grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	return WithVolumeServerClient(volumeServer, grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
-		stream, err := client.VolumeTailSender(ctx, &volume_server_pb.VolumeTailSenderRequest{
+		stream, err := client.VolumeTailSender(context.Background(), &volume_server_pb.VolumeTailSenderRequest{
 			VolumeId:           uint32(vid),
 			SinceNs:            sinceNs,
 			IdleTimeoutSeconds: uint32(idleTimeoutSeconds),
diff --git a/weed/pb/filer_pb/filer_pb_helper.go b/weed/pb/filer_pb/filer_pb_helper.go
index 349f07320..408caadcd 100644
--- a/weed/pb/filer_pb/filer_pb_helper.go
+++ b/weed/pb/filer_pb/filer_pb_helper.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/storage/needle"
 )
 
@@ -71,13 +72,15 @@ func AfterEntryDeserialization(chunks []*FileChunk) {
 	}
 }
 
-func CreateEntry(ctx context.Context, client SeaweedFilerClient, request *CreateEntryRequest) error {
-	resp, err := client.CreateEntry(ctx, request)
+func CreateEntry(client SeaweedFilerClient, request *CreateEntryRequest) error {
+	resp, err := client.CreateEntry(context.Background(), request)
 	if err != nil {
+		glog.V(1).Infof("create entry %s/%s %v: %v", request.Directory, request.Entry.Name, request.OExcl, err)
 		return fmt.Errorf("CreateEntry: %v", err)
 	}
 	if resp.Error != "" {
+		glog.V(1).Infof("create entry %s/%s %v: %v", request.Directory, request.Entry.Name, request.OExcl, err)
 		return fmt.Errorf("CreateEntry : %v", resp.Error)
 	}
-	return err
+	return nil
 }
diff --git a/weed/replication/replicator.go b/weed/replication/replicator.go
index a0ef6591c..a91c2ddd3 100644
--- a/weed/replication/replicator.go
+++ b/weed/replication/replicator.go
@@ -41,28 +41,28 @@ func (r *Replicator) Replicate(ctx context.Context, key string, message *filer_p
 	key = newKey
 	if message.OldEntry != nil && message.NewEntry == nil {
 		glog.V(4).Infof("deleting %v", key)
-		return r.sink.DeleteEntry(ctx, key, message.OldEntry.IsDirectory, message.DeleteChunks)
+		return r.sink.DeleteEntry(key, message.OldEntry.IsDirectory, message.DeleteChunks)
 	}
 	if message.OldEntry == nil && message.NewEntry != nil {
 		glog.V(4).Infof("creating %v", key)
-		return r.sink.CreateEntry(ctx, key, message.NewEntry)
+		return r.sink.CreateEntry(key, message.NewEntry)
 	}
 	if message.OldEntry == nil && message.NewEntry == nil {
 		glog.V(0).Infof("weird message %+v", message)
 		return nil
 	}
 
-	foundExisting, err := r.sink.UpdateEntry(ctx, key, message.OldEntry, message.NewParentPath, message.NewEntry, message.DeleteChunks)
+	foundExisting, err := r.sink.UpdateEntry(key, message.OldEntry, message.NewParentPath, message.NewEntry, message.DeleteChunks)
 	if foundExisting {
 		glog.V(4).Infof("updated %v", key)
 		return err
 	}
 
-	err = r.sink.DeleteEntry(ctx, key, message.OldEntry.IsDirectory, false)
+	err = r.sink.DeleteEntry(key, message.OldEntry.IsDirectory, false)
 	if err != nil {
 		return fmt.Errorf("delete old entry %v: %v", key, err)
 	}
 
 	glog.V(4).Infof("creating missing %v", key)
-	return r.sink.CreateEntry(ctx, key, message.NewEntry)
+	return r.sink.CreateEntry(key, message.NewEntry)
 }
diff --git a/weed/replication/sink/azuresink/azure_sink.go b/weed/replication/sink/azuresink/azure_sink.go
index a0b1a41ab..f7c0eef0d 100644
--- a/weed/replication/sink/azuresink/azure_sink.go
+++ b/weed/replication/sink/azuresink/azure_sink.go
@@ -70,7 +70,7 @@ func (g *AzureSink) initialize(accountName, accountKey, container, dir string) e
 	return nil
 }
 
-func (g *AzureSink) DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error {
+func (g *AzureSink) DeleteEntry(key string, isDirectory, deleteIncludeChunks bool) error {
 
 	key = cleanKey(key)
 
@@ -78,7 +78,7 @@ func (g *AzureSink) DeleteEntry(ctx context.Context, key string, isDirectory, de
 		key = key + "/"
 	}
 
-	if _, err := g.containerURL.NewBlobURL(key).Delete(ctx,
+	if _, err := g.containerURL.NewBlobURL(key).Delete(context.Background(),
 		azblob.DeleteSnapshotsOptionInclude, azblob.BlobAccessConditions{}); err != nil {
 		return fmt.Errorf("azure delete %s/%s: %v", g.container, key, err)
 	}
@@ -87,7 +87,7 @@ func (g *AzureSink) DeleteEntry(ctx context.Context, key string, isDirectory, de
 
 }
 
-func (g *AzureSink) CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error {
+func (g *AzureSink) CreateEntry(key string, entry *filer_pb.Entry) error {
 
 	key = cleanKey(key)
 
@@ -102,21 +102,21 @@ func (g *AzureSink) CreateEntry(ctx context.Context, key string, entry *filer_pb
 	// Azure Storage account's container.
 	appendBlobURL := g.containerURL.NewAppendBlobURL(key)
 
-	_, err := appendBlobURL.Create(ctx, azblob.BlobHTTPHeaders{}, azblob.Metadata{}, azblob.BlobAccessConditions{})
+	_, err := appendBlobURL.Create(context.Background(), azblob.BlobHTTPHeaders{}, azblob.Metadata{}, azblob.BlobAccessConditions{})
 	if err != nil {
 		return err
 	}
 
 	for _, chunk := range chunkViews {
 
-		fileUrl, err := g.filerSource.LookupFileId(ctx, chunk.FileId)
+		fileUrl, err := g.filerSource.LookupFileId(chunk.FileId)
 		if err != nil {
 			return err
 		}
 
 		var writeErr error
 		_, readErr := util.ReadUrlAsStream(fileUrl, chunk.Offset, int(chunk.Size), func(data []byte) {
-			_, writeErr = appendBlobURL.AppendBlock(ctx, bytes.NewReader(data), azblob.AppendBlobAccessConditions{}, nil)
+			_, writeErr = appendBlobURL.AppendBlock(context.Background(), bytes.NewReader(data), azblob.AppendBlobAccessConditions{}, nil)
 		})
 
 		if readErr != nil {
@@ -132,7 +132,7 @@ func (g *AzureSink) CreateEntry(ctx context.Context, key string, entry *filer_pb
 
 }
 
-func (g *AzureSink) UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
+func (g *AzureSink) UpdateEntry(key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
 	key = cleanKey(key)
 	// TODO improve efficiency
 	return false, nil
diff --git a/weed/replication/sink/b2sink/b2_sink.go b/weed/replication/sink/b2sink/b2_sink.go
index 8c80a64bd..d230719ce 100644
--- a/weed/replication/sink/b2sink/b2_sink.go
+++ b/weed/replication/sink/b2sink/b2_sink.go
@@ -58,7 +58,7 @@ func (g *B2Sink) initialize(accountId, accountKey, bucket, dir string) error {
 	return nil
 }
 
-func (g *B2Sink) DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error {
+func (g *B2Sink) DeleteEntry(key string, isDirectory, deleteIncludeChunks bool) error {
 
 	key = cleanKey(key)
 
@@ -66,18 +66,18 @@ func (g *B2Sink) DeleteEntry(ctx context.Context, key string, isDirectory, delet
 		key = key + "/"
 	}
 
-	bucket, err := g.client.Bucket(ctx, g.bucket)
+	bucket, err := g.client.Bucket(context.Background(), g.bucket)
 	if err != nil {
 		return err
 	}
 
 	targetObject := bucket.Object(key)
 
-	return targetObject.Delete(ctx)
+	return targetObject.Delete(context.Background())
 
 }
 
-func (g *B2Sink) CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error {
+func (g *B2Sink) CreateEntry(key string, entry *filer_pb.Entry) error {
 
 	key = cleanKey(key)
 
@@ -88,17 +88,17 @@ func (g *B2Sink) CreateEntry(ctx context.Context, key string, entry *filer_pb.En
 	totalSize := filer2.TotalSize(entry.Chunks)
 	chunkViews := filer2.ViewFromChunks(entry.Chunks, 0, int(totalSize))
 
-	bucket, err := g.client.Bucket(ctx, g.bucket)
+	bucket, err := g.client.Bucket(context.Background(), g.bucket)
 	if err != nil {
 		return err
 	}
 
 	targetObject := bucket.Object(key)
-	writer := targetObject.NewWriter(ctx)
+	writer := targetObject.NewWriter(context.Background())
 
 	for _, chunk := range chunkViews {
 
-		fileUrl, err := g.filerSource.LookupFileId(ctx, chunk.FileId)
+		fileUrl, err := g.filerSource.LookupFileId(chunk.FileId)
 		if err != nil {
 			return err
 		}
@@ -124,7 +124,7 @@ func (g *B2Sink) CreateEntry(ctx context.Context, key string, entry *filer_pb.En
 
 }
 
-func (g *B2Sink) UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
+func (g *B2Sink) UpdateEntry(key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
 
 	key = cleanKey(key)
 
diff --git a/weed/replication/sink/filersink/fetch_write.go b/weed/replication/sink/filersink/fetch_write.go
index 50f3f64d4..954e951c9 100644
--- a/weed/replication/sink/filersink/fetch_write.go
+++ b/weed/replication/sink/filersink/fetch_write.go
@@ -15,7 +15,7 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/util"
 )
 
-func (fs *FilerSink) replicateChunks(ctx context.Context, sourceChunks []*filer_pb.FileChunk, dir string) (replicatedChunks []*filer_pb.FileChunk, err error) {
+func (fs *FilerSink) replicateChunks(sourceChunks []*filer_pb.FileChunk, dir string) (replicatedChunks []*filer_pb.FileChunk, err error) {
 	if len(sourceChunks) == 0 {
 		return
 	}
@@ -24,7 +24,7 @@ func (fs *FilerSink) replicateChunks(ctx context.Context, sourceChunks []*filer_
 		wg.Add(1)
 		go func(chunk *filer_pb.FileChunk) {
 			defer wg.Done()
-			replicatedChunk, e := fs.replicateOneChunk(ctx, chunk, dir)
+			replicatedChunk, e := fs.replicateOneChunk(chunk, dir)
 			if e != nil {
 				err = e
 			}
@@ -36,9 +36,9 @@ func (fs *FilerSink) replicateChunks(ctx context.Context, sourceChunks []*filer_
 	return
 }
 
-func (fs *FilerSink) replicateOneChunk(ctx context.Context, sourceChunk *filer_pb.FileChunk, dir string) (*filer_pb.FileChunk, error) {
+func (fs *FilerSink) replicateOneChunk(sourceChunk *filer_pb.FileChunk, dir string) (*filer_pb.FileChunk, error) {
 
-	fileId, err := fs.fetchAndWrite(ctx, sourceChunk, dir)
+	fileId, err := fs.fetchAndWrite(sourceChunk, dir)
 	if err != nil {
 		return nil, fmt.Errorf("copy %s: %v", sourceChunk.GetFileIdString(), err)
 	}
@@ -53,9 +53,9 @@ func (fs *FilerSink) replicateOneChunk(ctx context.Context, sourceChunk *filer_p
 	}, nil
 }
 
-func (fs *FilerSink) fetchAndWrite(ctx context.Context, sourceChunk *filer_pb.FileChunk, dir string) (fileId string, err error) {
+func (fs *FilerSink) fetchAndWrite(sourceChunk *filer_pb.FileChunk, dir string) (fileId string, err error) {
 
-	filename, header, readCloser, err := fs.filerSource.ReadPart(ctx, sourceChunk.GetFileIdString())
+	filename, header, readCloser, err := fs.filerSource.ReadPart(sourceChunk.GetFileIdString())
 	if err != nil {
 		return "", fmt.Errorf("read part %s: %v", sourceChunk.GetFileIdString(), err)
 	}
@@ -64,7 +64,7 @@ func (fs *FilerSink) fetchAndWrite(ctx context.Context, sourceChunk *filer_pb.Fi
 	var host string
 	var auth security.EncodedJwt
 
-	if err := fs.withFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	if err := fs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.AssignVolumeRequest{
 			Count:       1,
@@ -75,7 +75,7 @@ func (fs *FilerSink) fetchAndWrite(ctx context.Context, sourceChunk *filer_pb.Fi
 			ParentPath:  dir,
 		}
 
-		resp, err := client.AssignVolume(ctx, request)
+		resp, err := client.AssignVolume(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("assign volume failure %v: %v", request, err)
 			return err
@@ -109,11 +109,11 @@ func (fs *FilerSink) fetchAndWrite(ctx context.Context, sourceChunk *filer_pb.Fi
 	return
 }
 
-func (fs *FilerSink) withFilerClient(ctx context.Context, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error {
+func (fs *FilerSink) withFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
 
-	return util.WithCachedGrpcClient(ctx, func(ctx context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(grpcConnection)
-		return fn(ctx, client)
+		return fn(client)
 	}, fs.grpcAddress, fs.grpcDialOption)
 
 }
diff --git a/weed/replication/sink/filersink/filer_sink.go b/weed/replication/sink/filersink/filer_sink.go
index cdc4f4a45..6b82b90df 100644
--- a/weed/replication/sink/filersink/filer_sink.go
+++ b/weed/replication/sink/filersink/filer_sink.go
@@ -64,8 +64,8 @@ func (fs *FilerSink) initialize(grpcAddress string, dir string,
 	return nil
 }
 
-func (fs *FilerSink) DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error {
-	return fs.withFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+func (fs *FilerSink) DeleteEntry(key string, isDirectory, deleteIncludeChunks bool) error {
+	return fs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		dir, name := filer2.FullPath(key).DirAndName()
 
@@ -76,7 +76,7 @@ func (fs *FilerSink) DeleteEntry(ctx context.Context, key string, isDirectory, d
 		}
 
 		glog.V(1).Infof("delete entry: %v", request)
-		_, err := client.DeleteEntry(ctx, request)
+		_, err := client.DeleteEntry(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("delete entry %s: %v", key, err)
 			return fmt.Errorf("delete entry %s: %v", key, err)
@@ -86,9 +86,9 @@ func (fs *FilerSink) DeleteEntry(ctx context.Context, key string, isDirectory, d
 	})
 }
 
-func (fs *FilerSink) CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error {
+func (fs *FilerSink) CreateEntry(key string, entry *filer_pb.Entry) error {
 
-	return fs.withFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return fs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		dir, name := filer2.FullPath(key).DirAndName()
 
@@ -98,14 +98,14 @@ func (fs *FilerSink) CreateEntry(ctx context.Context, key string, entry *filer_p
 			Name:      name,
 		}
 		glog.V(1).Infof("lookup: %v", lookupRequest)
-		if resp, err := client.LookupDirectoryEntry(ctx, lookupRequest); err == nil && resp.Entry != nil {
+		if resp, err := client.LookupDirectoryEntry(context.Background(), lookupRequest); err == nil && resp.Entry != nil {
 			if filer2.ETag(resp.Entry.Chunks) == filer2.ETag(entry.Chunks) {
 				glog.V(0).Infof("already replicated %s", key)
 				return nil
 			}
 		}
 
-		replicatedChunks, err := fs.replicateChunks(ctx, entry.Chunks, dir)
+		replicatedChunks, err := fs.replicateChunks(entry.Chunks, dir)
 
 		if err != nil {
 			glog.V(0).Infof("replicate entry chunks %s: %v", key, err)
@@ -125,7 +125,7 @@ func (fs *FilerSink) CreateEntry(ctx context.Context, key string, entry *filer_p
 		}
 
 		glog.V(1).Infof("create: %v", request)
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			glog.V(0).Infof("create entry %s: %v", key, err)
 			return fmt.Errorf("create entry %s: %v", key, err)
 		}
@@ -134,13 +134,13 @@ func (fs *FilerSink) CreateEntry(ctx context.Context, key string, entry *filer_p
 	})
 }
 
-func (fs *FilerSink) UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
+func (fs *FilerSink) UpdateEntry(key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
 
 	dir, name := filer2.FullPath(key).DirAndName()
 
 	// read existing entry
 	var existingEntry *filer_pb.Entry
-	err = fs.withFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = fs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Directory: dir,
@@ -148,7 +148,7 @@ func (fs *FilerSink) UpdateEntry(ctx context.Context, key string, oldEntry *file
 		}
 
 		glog.V(4).Infof("lookup entry: %v", request)
-		resp, err := client.LookupDirectoryEntry(ctx, request)
+		resp, err := client.LookupDirectoryEntry(context.Background(), request)
 		if err != nil {
 			glog.V(0).Infof("lookup %s: %v", key, err)
 			return err
@@ -187,7 +187,7 @@ func (fs *FilerSink) UpdateEntry(ctx context.Context, key string, oldEntry *file
 		}
 
 		// replicate the chunks that are new in the source
-		replicatedChunks, err := fs.replicateChunks(ctx, newChunks, newParentPath)
+		replicatedChunks, err := fs.replicateChunks(newChunks, newParentPath)
 		if err != nil {
 			return true, fmt.Errorf("replicte %s chunks error: %v", key, err)
 		}
@@ -195,14 +195,14 @@ func (fs *FilerSink) UpdateEntry(ctx context.Context, key string, oldEntry *file
 	}
 
 	// save updated meta data
-	return true, fs.withFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return true, fs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.UpdateEntryRequest{
 			Directory: newParentPath,
 			Entry:     existingEntry,
 		}
 
-		if _, err := client.UpdateEntry(ctx, request); err != nil {
+		if _, err := client.UpdateEntry(context.Background(), request); err != nil {
 			return fmt.Errorf("update existingEntry %s: %v", key, err)
 		}
 
diff --git a/weed/replication/sink/gcssink/gcs_sink.go b/weed/replication/sink/gcssink/gcs_sink.go
index 5aa978ab8..31dd5a85a 100644
--- a/weed/replication/sink/gcssink/gcs_sink.go
+++ b/weed/replication/sink/gcssink/gcs_sink.go
@@ -69,13 +69,13 @@ func (g *GcsSink) initialize(google_application_credentials, bucketName, dir str
 	return nil
 }
 
-func (g *GcsSink) DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error {
+func (g *GcsSink) DeleteEntry(key string, isDirectory, deleteIncludeChunks bool) error {
 
 	if isDirectory {
 		key = key + "/"
 	}
 
-	if err := g.client.Bucket(g.bucket).Object(key).Delete(ctx); err != nil {
+	if err := g.client.Bucket(g.bucket).Object(key).Delete(context.Background()); err != nil {
 		return fmt.Errorf("gcs delete %s%s: %v", g.bucket, key, err)
 	}
 
@@ -83,7 +83,7 @@ func (g *GcsSink) DeleteEntry(ctx context.Context, key string, isDirectory, dele
 
 }
 
-func (g *GcsSink) CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error {
+func (g *GcsSink) CreateEntry(key string, entry *filer_pb.Entry) error {
 
 	if entry.IsDirectory {
 		return nil
@@ -92,11 +92,11 @@ func (g *GcsSink) CreateEntry(ctx context.Context, key string, entry *filer_pb.E
 	totalSize := filer2.TotalSize(entry.Chunks)
 	chunkViews := filer2.ViewFromChunks(entry.Chunks, 0, int(totalSize))
 
-	wc := g.client.Bucket(g.bucket).Object(key).NewWriter(ctx)
+	wc := g.client.Bucket(g.bucket).Object(key).NewWriter(context.Background())
 
 	for _, chunk := range chunkViews {
 
-		fileUrl, err := g.filerSource.LookupFileId(ctx, chunk.FileId)
+		fileUrl, err := g.filerSource.LookupFileId(chunk.FileId)
 		if err != nil {
 			return err
 		}
@@ -119,7 +119,7 @@ func (g *GcsSink) CreateEntry(ctx context.Context, key string, entry *filer_pb.E
 
 }
 
-func (g *GcsSink) UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
+func (g *GcsSink) UpdateEntry(key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
 	// TODO improve efficiency
 	return false, nil
 }
diff --git a/weed/replication/sink/replication_sink.go b/weed/replication/sink/replication_sink.go
index 208bbdf87..6d85f660a 100644
--- a/weed/replication/sink/replication_sink.go
+++ b/weed/replication/sink/replication_sink.go
@@ -1,7 +1,6 @@
 package sink
 
 import (
-	"context"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/replication/source"
 	"github.com/chrislusf/seaweedfs/weed/util"
@@ -10,9 +9,9 @@ import (
 type ReplicationSink interface {
 	GetName() string
 	Initialize(configuration util.Configuration, prefix string) error
-	DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error
-	CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error
-	UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error)
+	DeleteEntry(key string, isDirectory, deleteIncludeChunks bool) error
+	CreateEntry(key string, entry *filer_pb.Entry) error
+	UpdateEntry(key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error)
 	GetSinkToDirectory() string
 	SetSourceFiler(s *source.FilerSource)
 }
diff --git a/weed/replication/sink/s3sink/s3_sink.go b/weed/replication/sink/s3sink/s3_sink.go
index e4e097c0f..fc3e6cd4d 100644
--- a/weed/replication/sink/s3sink/s3_sink.go
+++ b/weed/replication/sink/s3sink/s3_sink.go
@@ -11,6 +11,7 @@ import (
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/aws/aws-sdk-go/service/s3/s3iface"
+
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
@@ -77,7 +78,7 @@ func (s3sink *S3Sink) initialize(awsAccessKeyId, awsSecretAccessKey, region, buc
 	return nil
 }
 
-func (s3sink *S3Sink) DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error {
+func (s3sink *S3Sink) DeleteEntry(key string, isDirectory, deleteIncludeChunks bool) error {
 
 	key = cleanKey(key)
 
@@ -89,7 +90,7 @@ func (s3sink *S3Sink) DeleteEntry(ctx context.Context, key string, isDirectory,
 
 }
 
-func (s3sink *S3Sink) CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error {
+func (s3sink *S3Sink) CreateEntry(key string, entry *filer_pb.Entry) error {
 
 	key = cleanKey(key)
 
@@ -112,7 +113,7 @@ func (s3sink *S3Sink) CreateEntry(ctx context.Context, key string, entry *filer_
 		wg.Add(1)
 		go func(chunk *filer2.ChunkView) {
 			defer wg.Done()
-			if part, uploadErr := s3sink.uploadPart(ctx, key, uploadId, partId, chunk); uploadErr != nil {
+			if part, uploadErr := s3sink.uploadPart(context.Background(), key, uploadId, partId, chunk); uploadErr != nil {
 				err = uploadErr
 			} else {
 				parts = append(parts, part)
@@ -126,11 +127,11 @@ func (s3sink *S3Sink) CreateEntry(ctx context.Context, key string, entry *filer_
 		return err
 	}
 
-	return s3sink.completeMultipartUpload(ctx, key, uploadId, parts)
+	return s3sink.completeMultipartUpload(context.Background(), key, uploadId, parts)
 
 }
 
-func (s3sink *S3Sink) UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
+func (s3sink *S3Sink) UpdateEntry(key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error) {
 	key = cleanKey(key)
 	// TODO improve efficiency
 	return false, nil
diff --git a/weed/replication/sink/s3sink/s3_write.go b/weed/replication/sink/s3sink/s3_write.go
index 0a190b27d..9386169b8 100644
--- a/weed/replication/sink/s3sink/s3_write.go
+++ b/weed/replication/sink/s3sink/s3_write.go
@@ -157,7 +157,7 @@ func (s3sink *S3Sink) uploadPartCopy(key, uploadId string, partId int64, copySou
 }
 
 func (s3sink *S3Sink) buildReadSeeker(ctx context.Context, chunk *filer2.ChunkView) (io.ReadSeeker, error) {
-	fileUrl, err := s3sink.filerSource.LookupFileId(ctx, chunk.FileId)
+	fileUrl, err := s3sink.filerSource.LookupFileId(chunk.FileId)
 	if err != nil {
 		return nil, err
 	}
diff --git a/weed/replication/source/filer_source.go b/weed/replication/source/filer_source.go
index c3ea44671..11eb3afa1 100644
--- a/weed/replication/source/filer_source.go
+++ b/weed/replication/source/filer_source.go
@@ -40,16 +40,16 @@ func (fs *FilerSource) initialize(grpcAddress string, dir string) (err error) {
 	return nil
 }
 
-func (fs *FilerSource) LookupFileId(ctx context.Context, part string) (fileUrl string, err error) {
+func (fs *FilerSource) LookupFileId(part string) (fileUrl string, err error) {
 
 	vid2Locations := make(map[string]*filer_pb.Locations)
 
 	vid := volumeId(part)
 
-	err = fs.withFilerClient(ctx, fs.grpcDialOption, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = fs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		glog.V(4).Infof("read lookup volume id locations: %v", vid)
-		resp, err := client.LookupVolume(ctx, &filer_pb.LookupVolumeRequest{
+		resp, err := client.LookupVolume(context.Background(), &filer_pb.LookupVolumeRequest{
 			VolumeIds: []string{vid},
 		})
 		if err != nil {
@@ -78,9 +78,9 @@ func (fs *FilerSource) LookupFileId(ctx context.Context, part string) (fileUrl s
 	return
 }
 
-func (fs *FilerSource) ReadPart(ctx context.Context, part string) (filename string, header http.Header, readCloser io.ReadCloser, err error) {
+func (fs *FilerSource) ReadPart(part string) (filename string, header http.Header, readCloser io.ReadCloser, err error) {
 
-	fileUrl, err := fs.LookupFileId(ctx, part)
+	fileUrl, err := fs.LookupFileId(part)
 	if err != nil {
 		return "", nil, nil, err
 	}
@@ -90,11 +90,11 @@ func (fs *FilerSource) ReadPart(ctx context.Context, part string) (filename stri
 	return filename, header, readCloser, err
 }
 
-func (fs *FilerSource) withFilerClient(ctx context.Context, grpcDialOption grpc.DialOption, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error {
+func (fs *FilerSource) withFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
 
-	return util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, fs.grpcAddress, fs.grpcDialOption)
 
 }
diff --git a/weed/s3api/filer_util.go b/weed/s3api/filer_util.go
index 3c11b032c..f726de515 100644
--- a/weed/s3api/filer_util.go
+++ b/weed/s3api/filer_util.go
@@ -13,7 +13,7 @@ import (
 )
 
 func (s3a *S3ApiServer) mkdir(ctx context.Context, parentDirectoryPath string, dirName string, fn func(entry *filer_pb.Entry)) error {
-	return s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	return s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		entry := &filer_pb.Entry{
 			Name:        dirName,
@@ -37,7 +37,7 @@ func (s3a *S3ApiServer) mkdir(ctx context.Context, parentDirectoryPath string, d
 		}
 
 		glog.V(1).Infof("mkdir: %v", request)
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			glog.V(0).Infof("mkdir %v: %v", request, err)
 			return fmt.Errorf("mkdir %s/%s: %v", parentDirectoryPath, dirName, err)
 		}
@@ -47,7 +47,7 @@ func (s3a *S3ApiServer) mkdir(ctx context.Context, parentDirectoryPath string, d
 }
 
 func (s3a *S3ApiServer) mkFile(ctx context.Context, parentDirectoryPath string, fileName string, chunks []*filer_pb.FileChunk) error {
-	return s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	return s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		entry := &filer_pb.Entry{
 			Name:        fileName,
@@ -68,7 +68,7 @@ func (s3a *S3ApiServer) mkFile(ctx context.Context, parentDirectoryPath string,
 		}
 
 		glog.V(1).Infof("create file: %s/%s", parentDirectoryPath, fileName)
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			glog.V(0).Infof("create file %v:%v", request, err)
 			return fmt.Errorf("create file %s/%s: %v", parentDirectoryPath, fileName, err)
 		}
@@ -79,7 +79,7 @@ func (s3a *S3ApiServer) mkFile(ctx context.Context, parentDirectoryPath string,
 
 func (s3a *S3ApiServer) list(ctx context.Context, parentDirectoryPath, prefix, startFrom string, inclusive bool, limit int) (entries []*filer_pb.Entry, err error) {
 
-	err = s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	err = s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.ListEntriesRequest{
 			Directory:          parentDirectoryPath,
@@ -119,7 +119,7 @@ func (s3a *S3ApiServer) list(ctx context.Context, parentDirectoryPath, prefix, s
 
 func (s3a *S3ApiServer) rm(ctx context.Context, parentDirectoryPath string, entryName string, isDirectory, isDeleteData, isRecursive bool) error {
 
-	return s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	return s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.DeleteEntryRequest{
 			Directory:    parentDirectoryPath,
@@ -143,7 +143,7 @@ func (s3a *S3ApiServer) streamRemove(ctx context.Context, quiet bool,
 	fn func() (finished bool, parentDirectoryPath string, entryName string, isDeleteData, isRecursive bool),
 	respFn func(err string)) error {
 
-	return s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	return s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		stream, err := client.StreamDeleteEntries(ctx)
 		if err != nil {
@@ -196,7 +196,7 @@ func (s3a *S3ApiServer) streamRemove(ctx context.Context, quiet bool,
 
 func (s3a *S3ApiServer) exists(ctx context.Context, parentDirectoryPath string, entryName string, isDirectory bool) (exists bool, err error) {
 
-	err = s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	err = s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Directory: parentDirectoryPath,
diff --git a/weed/s3api/s3api_bucket_handlers.go b/weed/s3api/s3api_bucket_handlers.go
index 69275e212..91267be09 100644
--- a/weed/s3api/s3api_bucket_handlers.go
+++ b/weed/s3api/s3api_bucket_handlers.go
@@ -80,7 +80,7 @@ func (s3a *S3ApiServer) DeleteBucketHandler(w http.ResponseWriter, r *http.Reque
 	bucket := vars["bucket"]
 
 	ctx := context.Background()
-	err := s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	err := s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		// delete collection
 		deleteCollectionRequest := &filer_pb.DeleteCollectionRequest{
@@ -112,7 +112,7 @@ func (s3a *S3ApiServer) HeadBucketHandler(w http.ResponseWriter, r *http.Request
 
 	ctx := context.Background()
 
-	err := s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	err := s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Directory: s3a.option.BucketsPath,
diff --git a/weed/s3api/s3api_handlers.go b/weed/s3api/s3api_handlers.go
index 602f03e5c..81a260a63 100644
--- a/weed/s3api/s3api_handlers.go
+++ b/weed/s3api/s3api_handlers.go
@@ -2,17 +2,18 @@ package s3api
 
 import (
 	"bytes"
-	"context"
 	"encoding/base64"
 	"encoding/xml"
 	"fmt"
-	"github.com/chrislusf/seaweedfs/weed/glog"
-	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
-	"github.com/chrislusf/seaweedfs/weed/util"
-	"google.golang.org/grpc"
 	"net/http"
 	"net/url"
 	"time"
+
+	"google.golang.org/grpc"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/util"
 )
 
 type mimeType string
@@ -37,9 +38,9 @@ func encodeResponse(response interface{}) []byte {
 	return bytesBuffer.Bytes()
 }
 
-func (s3a *S3ApiServer) withFilerClient(ctx context.Context, fn func(filer_pb.SeaweedFilerClient) error) error {
+func (s3a *S3ApiServer) withFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
 
-	return util.WithCachedGrpcClient(ctx, func(ctx context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(grpcConnection)
 		return fn(client)
 	}, s3a.option.FilerGrpcAddress, s3a.option.GrpcDialOption)
diff --git a/weed/s3api/s3api_objects_list_handlers.go b/weed/s3api/s3api_objects_list_handlers.go
index 17ce2b547..97dc931ee 100644
--- a/weed/s3api/s3api_objects_list_handlers.go
+++ b/weed/s3api/s3api_objects_list_handlers.go
@@ -95,7 +95,7 @@ func (s3a *S3ApiServer) listFilerEntries(ctx context.Context, bucket, originalPr
 	}
 
 	// check filer
-	err = s3a.withFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	err = s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.ListEntriesRequest{
 			Directory:          fmt.Sprintf("%s/%s/%s", s3a.option.BucketsPath, bucket, dir),
diff --git a/weed/server/filer_grpc_server.go b/weed/server/filer_grpc_server.go
index 9bbabec26..c6ef04e85 100644
--- a/weed/server/filer_grpc_server.go
+++ b/weed/server/filer_grpc_server.go
@@ -300,8 +300,8 @@ func (fs *FilerServer) AssignVolume(ctx context.Context, req *filer_pb.AssignVol
 
 func (fs *FilerServer) DeleteCollection(ctx context.Context, req *filer_pb.DeleteCollectionRequest) (resp *filer_pb.DeleteCollectionResponse, err error) {
 
-	err = fs.filer.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		_, err := client.CollectionDelete(ctx, &master_pb.CollectionDeleteRequest{
+	err = fs.filer.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		_, err := client.CollectionDelete(context.Background(), &master_pb.CollectionDeleteRequest{
 			Name: req.GetCollection(),
 		})
 		return err
diff --git a/weed/server/filer_server.go b/weed/server/filer_server.go
index b0df851c9..5fc038e17 100644
--- a/weed/server/filer_server.go
+++ b/weed/server/filer_server.go
@@ -127,8 +127,8 @@ func maybeStartMetrics(fs *FilerServer, option *FilerOption) {
 }
 
 func readFilerConfiguration(grpcDialOption grpc.DialOption, masterGrpcAddress string) (metricsAddress string, metricsIntervalSec int, err error) {
-	err = operation.WithMasterServerClient(masterGrpcAddress, grpcDialOption, func(ctx context.Context, masterClient master_pb.SeaweedClient) error {
-		resp, err := masterClient.GetMasterConfiguration(ctx, &master_pb.GetMasterConfigurationRequest{})
+	err = operation.WithMasterServerClient(masterGrpcAddress, grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
+		resp, err := masterClient.GetMasterConfiguration(context.Background(), &master_pb.GetMasterConfigurationRequest{})
 		if err != nil {
 			return fmt.Errorf("get master %s configuration: %v", masterGrpcAddress, err)
 		}
diff --git a/weed/server/master_grpc_server_collection.go b/weed/server/master_grpc_server_collection.go
index f02b0f242..b92d6bcbe 100644
--- a/weed/server/master_grpc_server_collection.go
+++ b/weed/server/master_grpc_server_collection.go
@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"github.com/chrislusf/raft"
+
 	"github.com/chrislusf/seaweedfs/weed/operation"
 	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
 	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
@@ -57,8 +58,8 @@ func (ms *MasterServer) doDeleteNormalCollection(collectionName string) error {
 	}
 
 	for _, server := range collection.ListVolumeServers() {
-		err := operation.WithVolumeServerClient(server.Url(), ms.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
-			_, deleteErr := client.DeleteCollection(ctx, &volume_server_pb.DeleteCollectionRequest{
+		err := operation.WithVolumeServerClient(server.Url(), ms.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
+			_, deleteErr := client.DeleteCollection(context.Background(), &volume_server_pb.DeleteCollectionRequest{
 				Collection: collectionName,
 			})
 			return deleteErr
@@ -77,8 +78,8 @@ func (ms *MasterServer) doDeleteEcCollection(collectionName string) error {
 	listOfEcServers := ms.Topo.ListEcServersByCollection(collectionName)
 
 	for _, server := range listOfEcServers {
-		err := operation.WithVolumeServerClient(server, ms.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
-			_, deleteErr := client.DeleteCollection(ctx, &volume_server_pb.DeleteCollectionRequest{
+		err := operation.WithVolumeServerClient(server, ms.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
+			_, deleteErr := client.DeleteCollection(context.Background(), &volume_server_pb.DeleteCollectionRequest{
 				Collection: collectionName,
 			})
 			return deleteErr
diff --git a/weed/server/master_server.go b/weed/server/master_server.go
index f5f547a32..095008339 100644
--- a/weed/server/master_server.go
+++ b/weed/server/master_server.go
@@ -1,7 +1,6 @@
 package weed_server
 
 import (
-	"context"
 	"fmt"
 	"net/http"
 	"net/http/httputil"
@@ -89,7 +88,7 @@ func NewMasterServer(r *mux.Router, option *MasterOption, peers []string) *Maste
 		preallocateSize: preallocateSize,
 		clientChans:     make(map[string]chan *master_pb.VolumeLocation),
 		grpcDialOption:  grpcDialOption,
-		MasterClient:    wdclient.NewMasterClient(context.Background(), grpcDialOption, "master", peers),
+		MasterClient:    wdclient.NewMasterClient(grpcDialOption, "master", peers),
 	}
 	ms.bounedLeaderChan = make(chan int, 16)
 
diff --git a/weed/server/master_server_handlers_admin.go b/weed/server/master_server_handlers_admin.go
index 44a04cb86..2965a4863 100644
--- a/weed/server/master_server_handlers_admin.go
+++ b/weed/server/master_server_handlers_admin.go
@@ -25,8 +25,8 @@ func (ms *MasterServer) collectionDeleteHandler(w http.ResponseWriter, r *http.R
 		return
 	}
 	for _, server := range collection.ListVolumeServers() {
-		err := operation.WithVolumeServerClient(server.Url(), ms.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
-			_, deleteErr := client.DeleteCollection(ctx, &volume_server_pb.DeleteCollectionRequest{
+		err := operation.WithVolumeServerClient(server.Url(), ms.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
+			_, deleteErr := client.DeleteCollection(context.Background(), &volume_server_pb.DeleteCollectionRequest{
 				Collection: collection.Name,
 			})
 			return deleteErr
diff --git a/weed/server/volume_grpc_copy.go b/weed/server/volume_grpc_copy.go
index 6d74f8171..fcd13d364 100644
--- a/weed/server/volume_grpc_copy.go
+++ b/weed/server/volume_grpc_copy.go
@@ -41,9 +41,9 @@ func (vs *VolumeServer) VolumeCopy(ctx context.Context, req *volume_server_pb.Vo
 	//   confirm size and timestamp
 	var volFileInfoResp *volume_server_pb.ReadVolumeFileStatusResponse
 	var volumeFileName, idxFileName, datFileName string
-	err := operation.WithVolumeServerClient(req.SourceDataNode, vs.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	err := operation.WithVolumeServerClient(req.SourceDataNode, vs.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 		var err error
-		volFileInfoResp, err = client.ReadVolumeFileStatus(ctx,
+		volFileInfoResp, err = client.ReadVolumeFileStatus(context.Background(),
 			&volume_server_pb.ReadVolumeFileStatusRequest{
 				VolumeId: req.VolumeId,
 			})
diff --git a/weed/server/volume_grpc_erasure_coding.go b/weed/server/volume_grpc_erasure_coding.go
index 256e7c447..67efc0f6d 100644
--- a/weed/server/volume_grpc_erasure_coding.go
+++ b/weed/server/volume_grpc_erasure_coding.go
@@ -106,7 +106,7 @@ func (vs *VolumeServer) VolumeEcShardsCopy(ctx context.Context, req *volume_serv
 
 	baseFileName := storage.VolumeFileName(location.Directory, req.Collection, int(req.VolumeId))
 
-	err := operation.WithVolumeServerClient(req.SourceDataNode, vs.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	err := operation.WithVolumeServerClient(req.SourceDataNode, vs.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
 		// copy ec data slices
 		for _, shardId := range req.ShardIds {
diff --git a/weed/server/volume_grpc_file.go b/weed/server/volume_grpc_file.go
index c20aeb60f..4d71ddeb1 100644
--- a/weed/server/volume_grpc_file.go
+++ b/weed/server/volume_grpc_file.go
@@ -1,7 +1,6 @@
 package weed_server
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"strings"
@@ -45,7 +44,7 @@ func (vs *VolumeServer) FileGet(req *volume_server_pb.FileGetRequest, stream vol
 	if hasVolume {
 		count, err = vs.store.ReadVolumeNeedle(volumeId, n)
 	} else if hasEcVolume {
-		count, err = vs.store.ReadEcShardNeedle(context.Background(), volumeId, n)
+		count, err = vs.store.ReadEcShardNeedle(volumeId, n)
 	}
 
 	if err != nil || count < 0 {
diff --git a/weed/server/volume_server_handlers_read.go b/weed/server/volume_server_handlers_read.go
index d89d13a0d..40a951a74 100644
--- a/weed/server/volume_server_handlers_read.go
+++ b/weed/server/volume_server_handlers_read.go
@@ -2,7 +2,7 @@ package weed_server
 
 import (
 	"bytes"
-	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -15,8 +15,6 @@ import (
 	"strings"
 	"time"
 
-	"encoding/json"
-
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/images"
 	"github.com/chrislusf/seaweedfs/weed/operation"
@@ -86,7 +84,7 @@ func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
 	if hasVolume {
 		count, err = vs.store.ReadVolumeNeedle(volumeId, n)
 	} else if hasEcVolume {
-		count, err = vs.store.ReadEcShardNeedle(context.Background(), volumeId, n)
+		count, err = vs.store.ReadEcShardNeedle(volumeId, n)
 	}
 	// glog.V(4).Infoln("read bytes", count, "error", err)
 	if err != nil || count < 0 {
diff --git a/weed/server/webdav_server.go b/weed/server/webdav_server.go
index 7a7ab7a4b..959e50128 100644
--- a/weed/server/webdav_server.go
+++ b/weed/server/webdav_server.go
@@ -96,11 +96,11 @@ func NewWebDavFileSystem(option *WebDavOption) (webdav.FileSystem, error) {
 	}, nil
 }
 
-func (fs *WebDavFileSystem) WithFilerClient(ctx context.Context, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error {
+func (fs *WebDavFileSystem) WithFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
 
-	return util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, fs.option.FilerGrpcAddress, fs.option.GrpcDialOption)
 
 }
@@ -135,7 +135,7 @@ func (fs *WebDavFileSystem) Mkdir(ctx context.Context, fullDirPath string, perm
 		return os.ErrExist
 	}
 
-	return fs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return fs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 		dir, name := filer2.FullPath(fullDirPath).DirAndName()
 		request := &filer_pb.CreateEntryRequest{
 			Directory: dir,
@@ -153,7 +153,7 @@ func (fs *WebDavFileSystem) Mkdir(ctx context.Context, fullDirPath string, perm
 		}
 
 		glog.V(1).Infof("mkdir: %v", request)
-		if err := filer_pb.CreateEntry(ctx, client, request); err != nil {
+		if err := filer_pb.CreateEntry(client, request); err != nil {
 			return fmt.Errorf("mkdir %s/%s: %v", dir, name, err)
 		}
 
@@ -184,8 +184,8 @@ func (fs *WebDavFileSystem) OpenFile(ctx context.Context, fullFilePath string, f
 		}
 
 		dir, name := filer2.FullPath(fullFilePath).DirAndName()
-		err = fs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-			if err := filer_pb.CreateEntry(ctx, client, &filer_pb.CreateEntryRequest{
+		err = fs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+			if err := filer_pb.CreateEntry(client, &filer_pb.CreateEntryRequest{
 				Directory: dir,
 				Entry: &filer_pb.Entry{
 					Name:        name,
@@ -249,7 +249,7 @@ func (fs *WebDavFileSystem) removeAll(ctx context.Context, fullFilePath string)
 		//_, err = fs.db.Exec(`delete from filesystem where fullFilePath = ?`, fullFilePath)
 	}
 	dir, name := filer2.FullPath(fullFilePath).DirAndName()
-	err = fs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = fs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.DeleteEntryRequest{
 			Directory:    dir,
@@ -308,7 +308,7 @@ func (fs *WebDavFileSystem) Rename(ctx context.Context, oldName, newName string)
 	oldDir, oldBaseName := filer2.FullPath(oldName).DirAndName()
 	newDir, newBaseName := filer2.FullPath(newName).DirAndName()
 
-	return fs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return fs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.AtomicRenameEntryRequest{
 			OldDirectory: oldDir,
@@ -336,7 +336,7 @@ func (fs *WebDavFileSystem) stat(ctx context.Context, fullFilePath string) (os.F
 	fullpath := filer2.FullPath(fullFilePath)
 
 	var fi FileInfo
-	entry, err := filer2.GetEntry(ctx, fs, fullpath)
+	entry, err := filer2.GetEntry(fs, fullpath)
 	if entry == nil {
 		return nil, os.ErrNotExist
 	}
@@ -372,7 +372,7 @@ func (f *WebDavFile) Write(buf []byte) (int, error) {
 	var err error
 	ctx := context.Background()
 	if f.entry == nil {
-		f.entry, err = filer2.GetEntry(ctx, f.fs, filer2.FullPath(f.name))
+		f.entry, err = filer2.GetEntry(f.fs, filer2.FullPath(f.name))
 	}
 
 	if f.entry == nil {
@@ -386,7 +386,7 @@ func (f *WebDavFile) Write(buf []byte) (int, error) {
 	var auth security.EncodedJwt
 	var collection, replication string
 
-	if err = f.fs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	if err = f.fs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.AssignVolumeRequest{
 			Count:       1,
@@ -434,7 +434,7 @@ func (f *WebDavFile) Write(buf []byte) (int, error) {
 
 	f.entry.Chunks = append(f.entry.Chunks, chunk)
 
-	err = f.fs.WithFilerClient(ctx, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = f.fs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 		f.entry.Attributes.Mtime = time.Now().Unix()
 		f.entry.Attributes.Collection = collection
 		f.entry.Attributes.Replication = replication
@@ -474,10 +474,9 @@ func (f *WebDavFile) Close() error {
 func (f *WebDavFile) Read(p []byte) (readSize int, err error) {
 
 	glog.V(2).Infof("WebDavFileSystem.Read %v", f.name)
-	ctx := context.Background()
 
 	if f.entry == nil {
-		f.entry, err = filer2.GetEntry(ctx, f.fs, filer2.FullPath(f.name))
+		f.entry, err = filer2.GetEntry(f.fs, filer2.FullPath(f.name))
 	}
 	if f.entry == nil {
 		return 0, err
@@ -493,7 +492,7 @@ func (f *WebDavFile) Read(p []byte) (readSize int, err error) {
 	}
 	chunkViews := filer2.ViewFromVisibleIntervals(f.entryViewCache, f.off, len(p))
 
-	totalRead, err := filer2.ReadIntoBuffer(ctx, f.fs, filer2.FullPath(f.name), p, chunkViews, f.off)
+	totalRead, err := filer2.ReadIntoBuffer(f.fs, filer2.FullPath(f.name), p, chunkViews, f.off)
 	if err != nil {
 		return 0, err
 	}
@@ -512,11 +511,10 @@ func (f *WebDavFile) Read(p []byte) (readSize int, err error) {
 func (f *WebDavFile) Readdir(count int) (ret []os.FileInfo, err error) {
 
 	glog.V(2).Infof("WebDavFileSystem.Readdir %v count %d", f.name, count)
-	ctx := context.Background()
 
 	dir, _ := filer2.FullPath(f.name).DirAndName()
 
-	err = filer2.ReadDirAllEntries(ctx, f.fs, filer2.FullPath(dir), "", func(entry *filer_pb.Entry, isLast bool) {
+	err = filer2.ReadDirAllEntries(f.fs, filer2.FullPath(dir), "", func(entry *filer_pb.Entry, isLast bool) {
 		fi := FileInfo{
 			size:          int64(filer2.TotalSize(entry.GetChunks())),
 			name:          entry.Name,
diff --git a/weed/shell/command_bucket_create.go b/weed/shell/command_bucket_create.go
index 603e9c564..3546528aa 100644
--- a/weed/shell/command_bucket_create.go
+++ b/weed/shell/command_bucket_create.go
@@ -48,11 +48,9 @@ func (c *commandBucketCreate) Do(args []string, commandEnv *CommandEnv, writer i
 		return parseErr
 	}
 
-	ctx := context.Background()
+	err = commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
-	err = commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-
-		resp, err := client.GetFilerConfiguration(ctx, &filer_pb.GetFilerConfigurationRequest{})
+		resp, err := client.GetFilerConfiguration(context.Background(), &filer_pb.GetFilerConfigurationRequest{})
 		if err != nil {
 			return fmt.Errorf("get filer %s:%d configuration: %v", filerServer, filerPort, err)
 		}
@@ -72,7 +70,7 @@ func (c *commandBucketCreate) Do(args []string, commandEnv *CommandEnv, writer i
 			},
 		}
 
-		if err := filer_pb.CreateEntry(ctx, client, &filer_pb.CreateEntryRequest{
+		if err := filer_pb.CreateEntry(client, &filer_pb.CreateEntryRequest{
 			Directory: filerBucketsPath,
 			Entry:     entry,
 		}); err != nil {
diff --git a/weed/shell/command_bucket_delete.go b/weed/shell/command_bucket_delete.go
index 9e814ccf9..c57ce7221 100644
--- a/weed/shell/command_bucket_delete.go
+++ b/weed/shell/command_bucket_delete.go
@@ -44,17 +44,15 @@ func (c *commandBucketDelete) Do(args []string, commandEnv *CommandEnv, writer i
 		return parseErr
 	}
 
-	ctx := context.Background()
+	err = commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
-	err = commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-
-		resp, err := client.GetFilerConfiguration(ctx, &filer_pb.GetFilerConfigurationRequest{})
+		resp, err := client.GetFilerConfiguration(context.Background(), &filer_pb.GetFilerConfigurationRequest{})
 		if err != nil {
 			return fmt.Errorf("get filer %s:%d configuration: %v", filerServer, filerPort, err)
 		}
 		filerBucketsPath := resp.DirBuckets
 
-		if _, err := client.DeleteEntry(ctx, &filer_pb.DeleteEntryRequest{
+		if _, err := client.DeleteEntry(context.Background(), &filer_pb.DeleteEntryRequest{
 			Directory:            filerBucketsPath,
 			Name:                 *bucketName,
 			IsDeleteData:         false,
diff --git a/weed/shell/command_bucket_list.go b/weed/shell/command_bucket_list.go
index 32198c29d..5eb5972ce 100644
--- a/weed/shell/command_bucket_list.go
+++ b/weed/shell/command_bucket_list.go
@@ -39,17 +39,15 @@ func (c *commandBucketList) Do(args []string, commandEnv *CommandEnv, writer io.
 		return parseErr
 	}
 
-	ctx := context.Background()
+	err = commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
-	err = commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
-
-		resp, err := client.GetFilerConfiguration(ctx, &filer_pb.GetFilerConfigurationRequest{})
+		resp, err := client.GetFilerConfiguration(context.Background(), &filer_pb.GetFilerConfigurationRequest{})
 		if err != nil {
 			return fmt.Errorf("get filer %s:%d configuration: %v", filerServer, filerPort, err)
 		}
 		filerBucketsPath := resp.DirBuckets
 
-		stream, err := client.ListEntries(ctx, &filer_pb.ListEntriesRequest{
+		stream, err := client.ListEntries(context.Background(), &filer_pb.ListEntriesRequest{
 			Directory: filerBucketsPath,
 			Limit:     math.MaxUint32,
 		})
diff --git a/weed/shell/command_collection_delete.go b/weed/shell/command_collection_delete.go
index fbaddcd51..4b3d7f0be 100644
--- a/weed/shell/command_collection_delete.go
+++ b/weed/shell/command_collection_delete.go
@@ -34,9 +34,8 @@ func (c *commandCollectionDelete) Do(args []string, commandEnv *CommandEnv, writ
 
 	collectionName := args[0]
 
-	ctx := context.Background()
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		_, err = client.CollectionDelete(ctx, &master_pb.CollectionDeleteRequest{
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		_, err = client.CollectionDelete(context.Background(), &master_pb.CollectionDeleteRequest{
 			Name: collectionName,
 		})
 		return err
diff --git a/weed/shell/command_collection_list.go b/weed/shell/command_collection_list.go
index c4325c66f..2a114e61b 100644
--- a/weed/shell/command_collection_list.go
+++ b/weed/shell/command_collection_list.go
@@ -41,9 +41,8 @@ func (c *commandCollectionList) Do(args []string, commandEnv *CommandEnv, writer
 
 func ListCollectionNames(commandEnv *CommandEnv, includeNormalVolumes, includeEcVolumes bool) (collections []string, err error) {
 	var resp *master_pb.CollectionListResponse
-	ctx := context.Background()
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.CollectionList(ctx, &master_pb.CollectionListRequest{
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.CollectionList(context.Background(), &master_pb.CollectionListRequest{
 			IncludeNormalVolumes: includeNormalVolumes,
 			IncludeEcVolumes:     includeEcVolumes,
 		})
diff --git a/weed/shell/command_ec_balance.go b/weed/shell/command_ec_balance.go
index 96599372e..7230a869f 100644
--- a/weed/shell/command_ec_balance.go
+++ b/weed/shell/command_ec_balance.go
@@ -107,10 +107,8 @@ func (c *commandEcBalance) Do(args []string, commandEnv *CommandEnv, writer io.W
 		return nil
 	}
 
-	ctx := context.Background()
-
 	// collect all ec nodes
-	allEcNodes, totalFreeEcSlots, err := collectEcNodes(ctx, commandEnv, *dc)
+	allEcNodes, totalFreeEcSlots, err := collectEcNodes(commandEnv, *dc)
 	if err != nil {
 		return err
 	}
@@ -138,7 +136,7 @@ func (c *commandEcBalance) Do(args []string, commandEnv *CommandEnv, writer io.W
 		}
 	}
 
-	if err := balanceEcRacks(ctx, commandEnv, racks, *applyBalancing); err != nil {
+	if err := balanceEcRacks(commandEnv, racks, *applyBalancing); err != nil {
 		return fmt.Errorf("balance ec racks: %v", err)
 	}
 
@@ -170,11 +168,11 @@ func balanceEcVolumes(commandEnv *CommandEnv, collection string, allEcNodes []*E
 		return fmt.Errorf("delete duplicated collection %s ec shards: %v", collection, err)
 	}
 
-	if err := balanceEcShardsAcrossRacks(ctx, commandEnv, allEcNodes, racks, collection, applyBalancing); err != nil {
+	if err := balanceEcShardsAcrossRacks(commandEnv, allEcNodes, racks, collection, applyBalancing); err != nil {
 		return fmt.Errorf("balance across racks collection %s ec shards: %v", collection, err)
 	}
 
-	if err := balanceEcShardsWithinRacks(ctx, commandEnv, allEcNodes, racks, collection, applyBalancing); err != nil {
+	if err := balanceEcShardsWithinRacks(commandEnv, allEcNodes, racks, collection, applyBalancing); err != nil {
 		return fmt.Errorf("balance across racks collection %s ec shards: %v", collection, err)
 	}
 
@@ -186,14 +184,14 @@ func deleteDuplicatedEcShards(ctx context.Context, commandEnv *CommandEnv, allEc
 	vidLocations := collectVolumeIdToEcNodes(allEcNodes)
 	// deduplicate ec shards
 	for vid, locations := range vidLocations {
-		if err := doDeduplicateEcShards(ctx, commandEnv, collection, vid, locations, applyBalancing); err != nil {
+		if err := doDeduplicateEcShards(commandEnv, collection, vid, locations, applyBalancing); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func doDeduplicateEcShards(ctx context.Context, commandEnv *CommandEnv, collection string, vid needle.VolumeId, locations []*EcNode, applyBalancing bool) error {
+func doDeduplicateEcShards(commandEnv *CommandEnv, collection string, vid needle.VolumeId, locations []*EcNode, applyBalancing bool) error {
 
 	// check whether this volume has ecNodes that are over average
 	shardToLocations := make([][]*EcNode, erasure_coding.TotalShardsCount)
@@ -215,10 +213,10 @@ func doDeduplicateEcShards(ctx context.Context, commandEnv *CommandEnv, collecti
 
 		duplicatedShardIds := []uint32{uint32(shardId)}
 		for _, ecNode := range ecNodes[1:] {
-			if err := unmountEcShards(ctx, commandEnv.option.GrpcDialOption, vid, ecNode.info.Id, duplicatedShardIds); err != nil {
+			if err := unmountEcShards(commandEnv.option.GrpcDialOption, vid, ecNode.info.Id, duplicatedShardIds); err != nil {
 				return err
 			}
-			if err := sourceServerDeleteEcShards(ctx, commandEnv.option.GrpcDialOption, collection, vid, ecNode.info.Id, duplicatedShardIds); err != nil {
+			if err := sourceServerDeleteEcShards(commandEnv.option.GrpcDialOption, collection, vid, ecNode.info.Id, duplicatedShardIds); err != nil {
 				return err
 			}
 			ecNode.deleteEcVolumeShards(vid, duplicatedShardIds)
@@ -227,19 +225,19 @@ func doDeduplicateEcShards(ctx context.Context, commandEnv *CommandEnv, collecti
 	return nil
 }
 
-func balanceEcShardsAcrossRacks(ctx context.Context, commandEnv *CommandEnv, allEcNodes []*EcNode, racks map[RackId]*EcRack, collection string, applyBalancing bool) error {
+func balanceEcShardsAcrossRacks(commandEnv *CommandEnv, allEcNodes []*EcNode, racks map[RackId]*EcRack, collection string, applyBalancing bool) error {
 	// collect vid => []ecNode, since previous steps can change the locations
 	vidLocations := collectVolumeIdToEcNodes(allEcNodes)
 	// spread the ec shards evenly
 	for vid, locations := range vidLocations {
-		if err := doBalanceEcShardsAcrossRacks(ctx, commandEnv, collection, vid, locations, racks, applyBalancing); err != nil {
+		if err := doBalanceEcShardsAcrossRacks(commandEnv, collection, vid, locations, racks, applyBalancing); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func doBalanceEcShardsAcrossRacks(ctx context.Context, commandEnv *CommandEnv, collection string, vid needle.VolumeId, locations []*EcNode, racks map[RackId]*EcRack, applyBalancing bool) error {
+func doBalanceEcShardsAcrossRacks(commandEnv *CommandEnv, collection string, vid needle.VolumeId, locations []*EcNode, racks map[RackId]*EcRack, applyBalancing bool) error {
 
 	// calculate average number of shards an ec rack should have for one volume
 	averageShardsPerEcRack := ceilDivide(erasure_coding.TotalShardsCount, len(racks))
@@ -274,7 +272,7 @@ func doBalanceEcShardsAcrossRacks(ctx context.Context, commandEnv *CommandEnv, c
 		for _, n := range racks[rackId].ecNodes {
 			possibleDestinationEcNodes = append(possibleDestinationEcNodes, n)
 		}
-		err := pickOneEcNodeAndMoveOneShard(ctx, commandEnv, averageShardsPerEcRack, ecNode, collection, vid, shardId, possibleDestinationEcNodes, applyBalancing)
+		err := pickOneEcNodeAndMoveOneShard(commandEnv, averageShardsPerEcRack, ecNode, collection, vid, shardId, possibleDestinationEcNodes, applyBalancing)
 		if err != nil {
 			return err
 		}
@@ -306,7 +304,7 @@ func pickOneRack(rackToEcNodes map[RackId]*EcRack, rackToShardCount map[string]i
 	return ""
 }
 
-func balanceEcShardsWithinRacks(ctx context.Context, commandEnv *CommandEnv, allEcNodes []*EcNode, racks map[RackId]*EcRack, collection string, applyBalancing bool) error {
+func balanceEcShardsWithinRacks(commandEnv *CommandEnv, allEcNodes []*EcNode, racks map[RackId]*EcRack, collection string, applyBalancing bool) error {
 	// collect vid => []ecNode, since previous steps can change the locations
 	vidLocations := collectVolumeIdToEcNodes(allEcNodes)
 
@@ -330,7 +328,7 @@ func balanceEcShardsWithinRacks(ctx context.Context, commandEnv *CommandEnv, all
 			}
 			sourceEcNodes := rackEcNodesWithVid[rackId]
 			averageShardsPerEcNode := ceilDivide(rackToShardCount[rackId], len(possibleDestinationEcNodes))
-			if err := doBalanceEcShardsWithinOneRack(ctx, commandEnv, averageShardsPerEcNode, collection, vid, sourceEcNodes, possibleDestinationEcNodes, applyBalancing); err != nil {
+			if err := doBalanceEcShardsWithinOneRack(commandEnv, averageShardsPerEcNode, collection, vid, sourceEcNodes, possibleDestinationEcNodes, applyBalancing); err != nil {
 				return err
 			}
 		}
@@ -338,7 +336,7 @@ func balanceEcShardsWithinRacks(ctx context.Context, commandEnv *CommandEnv, all
 	return nil
 }
 
-func doBalanceEcShardsWithinOneRack(ctx context.Context, commandEnv *CommandEnv, averageShardsPerEcNode int, collection string, vid needle.VolumeId, existingLocations, possibleDestinationEcNodes []*EcNode, applyBalancing bool) error {
+func doBalanceEcShardsWithinOneRack(commandEnv *CommandEnv, averageShardsPerEcNode int, collection string, vid needle.VolumeId, existingLocations, possibleDestinationEcNodes []*EcNode, applyBalancing bool) error {
 
 	for _, ecNode := range existingLocations {
 
@@ -353,7 +351,7 @@ func doBalanceEcShardsWithinOneRack(ctx context.Context, commandEnv *CommandEnv,
 
 			fmt.Printf("%s has %d overlimit, moving ec shard %d.%d\n", ecNode.info.Id, overLimitCount, vid, shardId)
 
-			err := pickOneEcNodeAndMoveOneShard(ctx, commandEnv, averageShardsPerEcNode, ecNode, collection, vid, shardId, possibleDestinationEcNodes, applyBalancing)
+			err := pickOneEcNodeAndMoveOneShard(commandEnv, averageShardsPerEcNode, ecNode, collection, vid, shardId, possibleDestinationEcNodes, applyBalancing)
 			if err != nil {
 				return err
 			}
@@ -365,18 +363,18 @@ func doBalanceEcShardsWithinOneRack(ctx context.Context, commandEnv *CommandEnv,
 	return nil
 }
 
-func balanceEcRacks(ctx context.Context, commandEnv *CommandEnv, racks map[RackId]*EcRack, applyBalancing bool) error {
+func balanceEcRacks(commandEnv *CommandEnv, racks map[RackId]*EcRack, applyBalancing bool) error {
 
 	// balance one rack for all ec shards
 	for _, ecRack := range racks {
-		if err := doBalanceEcRack(ctx, commandEnv, ecRack, applyBalancing); err != nil {
+		if err := doBalanceEcRack(commandEnv, ecRack, applyBalancing); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func doBalanceEcRack(ctx context.Context, commandEnv *CommandEnv, ecRack *EcRack, applyBalancing bool) error {
+func doBalanceEcRack(commandEnv *CommandEnv, ecRack *EcRack, applyBalancing bool) error {
 
 	if len(ecRack.ecNodes) <= 1 {
 		return nil
@@ -421,7 +419,7 @@ func doBalanceEcRack(ctx context.Context, commandEnv *CommandEnv, ecRack *EcRack
 
 						fmt.Printf("%s moves ec shards %d.%d to %s\n", fullNode.info.Id, shards.Id, shardId, emptyNode.info.Id)
 
-						err := moveMountedShardToEcNode(ctx, commandEnv, fullNode, shards.Collection, needle.VolumeId(shards.Id), shardId, emptyNode, applyBalancing)
+						err := moveMountedShardToEcNode(commandEnv, fullNode, shards.Collection, needle.VolumeId(shards.Id), shardId, emptyNode, applyBalancing)
 						if err != nil {
 							return err
 						}
@@ -440,7 +438,7 @@ func doBalanceEcRack(ctx context.Context, commandEnv *CommandEnv, ecRack *EcRack
 	return nil
 }
 
-func pickOneEcNodeAndMoveOneShard(ctx context.Context, commandEnv *CommandEnv, averageShardsPerEcNode int, existingLocation *EcNode, collection string, vid needle.VolumeId, shardId erasure_coding.ShardId, possibleDestinationEcNodes []*EcNode, applyBalancing bool) error {
+func pickOneEcNodeAndMoveOneShard(commandEnv *CommandEnv, averageShardsPerEcNode int, existingLocation *EcNode, collection string, vid needle.VolumeId, shardId erasure_coding.ShardId, possibleDestinationEcNodes []*EcNode, applyBalancing bool) error {
 
 	sortEcNodesByFreeslotsDecending(possibleDestinationEcNodes)
 
@@ -458,7 +456,7 @@ func pickOneEcNodeAndMoveOneShard(ctx context.Context, commandEnv *CommandEnv, a
 
 		fmt.Printf("%s moves ec shard %d.%d to %s\n", existingLocation.info.Id, vid, shardId, destEcNode.info.Id)
 
-		err := moveMountedShardToEcNode(ctx, commandEnv, existingLocation, collection, vid, shardId, destEcNode, applyBalancing)
+		err := moveMountedShardToEcNode(commandEnv, existingLocation, collection, vid, shardId, destEcNode, applyBalancing)
 		if err != nil {
 			return err
 		}
diff --git a/weed/shell/command_ec_common.go b/weed/shell/command_ec_common.go
index e187d5a3b..0db119d3c 100644
--- a/weed/shell/command_ec_common.go
+++ b/weed/shell/command_ec_common.go
@@ -15,26 +15,26 @@ import (
 	"google.golang.org/grpc"
 )
 
-func moveMountedShardToEcNode(ctx context.Context, commandEnv *CommandEnv, existingLocation *EcNode, collection string, vid needle.VolumeId, shardId erasure_coding.ShardId, destinationEcNode *EcNode, applyBalancing bool) (err error) {
+func moveMountedShardToEcNode(commandEnv *CommandEnv, existingLocation *EcNode, collection string, vid needle.VolumeId, shardId erasure_coding.ShardId, destinationEcNode *EcNode, applyBalancing bool) (err error) {
 
 	copiedShardIds := []uint32{uint32(shardId)}
 
 	if applyBalancing {
 
 		// ask destination node to copy shard and the ecx file from source node, and mount it
-		copiedShardIds, err = oneServerCopyAndMountEcShardsFromSource(ctx, commandEnv.option.GrpcDialOption, destinationEcNode, []uint32{uint32(shardId)}, vid, collection, existingLocation.info.Id)
+		copiedShardIds, err = oneServerCopyAndMountEcShardsFromSource(commandEnv.option.GrpcDialOption, destinationEcNode, []uint32{uint32(shardId)}, vid, collection, existingLocation.info.Id)
 		if err != nil {
 			return err
 		}
 
 		// unmount the to be deleted shards
-		err = unmountEcShards(ctx, commandEnv.option.GrpcDialOption, vid, existingLocation.info.Id, copiedShardIds)
+		err = unmountEcShards(commandEnv.option.GrpcDialOption, vid, existingLocation.info.Id, copiedShardIds)
 		if err != nil {
 			return err
 		}
 
 		// ask source node to delete the shard, and maybe the ecx file
-		err = sourceServerDeleteEcShards(ctx, commandEnv.option.GrpcDialOption, collection, vid, existingLocation.info.Id, copiedShardIds)
+		err = sourceServerDeleteEcShards(commandEnv.option.GrpcDialOption, collection, vid, existingLocation.info.Id, copiedShardIds)
 		if err != nil {
 			return err
 		}
@@ -50,18 +50,18 @@ func moveMountedShardToEcNode(ctx context.Context, commandEnv *CommandEnv, exist
 
 }
 
-func oneServerCopyAndMountEcShardsFromSource(ctx context.Context, grpcDialOption grpc.DialOption,
+func oneServerCopyAndMountEcShardsFromSource(grpcDialOption grpc.DialOption,
 	targetServer *EcNode, shardIdsToCopy []uint32,
 	volumeId needle.VolumeId, collection string, existingLocation string) (copiedShardIds []uint32, err error) {
 
 	fmt.Printf("allocate %d.%v %s => %s\n", volumeId, shardIdsToCopy, existingLocation, targetServer.info.Id)
 
-	err = operation.WithVolumeServerClient(targetServer.info.Id, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
+	err = operation.WithVolumeServerClient(targetServer.info.Id, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
 
 		if targetServer.info.Id != existingLocation {
 
 			fmt.Printf("copy %d.%v %s => %s\n", volumeId, shardIdsToCopy, existingLocation, targetServer.info.Id)
-			_, copyErr := volumeServerClient.VolumeEcShardsCopy(ctx, &volume_server_pb.VolumeEcShardsCopyRequest{
+			_, copyErr := volumeServerClient.VolumeEcShardsCopy(context.Background(), &volume_server_pb.VolumeEcShardsCopyRequest{
 				VolumeId:       uint32(volumeId),
 				Collection:     collection,
 				ShardIds:       shardIdsToCopy,
@@ -76,7 +76,7 @@ func oneServerCopyAndMountEcShardsFromSource(ctx context.Context, grpcDialOption
 		}
 
 		fmt.Printf("mount %d.%v on %s\n", volumeId, shardIdsToCopy, targetServer.info.Id)
-		_, mountErr := volumeServerClient.VolumeEcShardsMount(ctx, &volume_server_pb.VolumeEcShardsMountRequest{
+		_, mountErr := volumeServerClient.VolumeEcShardsMount(context.Background(), &volume_server_pb.VolumeEcShardsMountRequest{
 			VolumeId:   uint32(volumeId),
 			Collection: collection,
 			ShardIds:   shardIdsToCopy,
@@ -178,12 +178,12 @@ type EcRack struct {
 	freeEcSlot int
 }
 
-func collectEcNodes(ctx context.Context, commandEnv *CommandEnv, selectedDataCenter string) (ecNodes []*EcNode, totalFreeEcSlots int, err error) {
+func collectEcNodes(commandEnv *CommandEnv, selectedDataCenter string) (ecNodes []*EcNode, totalFreeEcSlots int, err error) {
 
 	// list all possible locations
 	var resp *master_pb.VolumeListResponse
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
@@ -211,13 +211,12 @@ func collectEcNodes(ctx context.Context, commandEnv *CommandEnv, selectedDataCen
 	return
 }
 
-func sourceServerDeleteEcShards(ctx context.Context, grpcDialOption grpc.DialOption,
-	collection string, volumeId needle.VolumeId, sourceLocation string, toBeDeletedShardIds []uint32) error {
+func sourceServerDeleteEcShards(grpcDialOption grpc.DialOption, collection string, volumeId needle.VolumeId, sourceLocation string, toBeDeletedShardIds []uint32) error {
 
 	fmt.Printf("delete %d.%v from %s\n", volumeId, toBeDeletedShardIds, sourceLocation)
 
-	return operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, deleteErr := volumeServerClient.VolumeEcShardsDelete(ctx, &volume_server_pb.VolumeEcShardsDeleteRequest{
+	return operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, deleteErr := volumeServerClient.VolumeEcShardsDelete(context.Background(), &volume_server_pb.VolumeEcShardsDeleteRequest{
 			VolumeId:   uint32(volumeId),
 			Collection: collection,
 			ShardIds:   toBeDeletedShardIds,
@@ -227,13 +226,12 @@ func sourceServerDeleteEcShards(ctx context.Context, grpcDialOption grpc.DialOpt
 
 }
 
-func unmountEcShards(ctx context.Context, grpcDialOption grpc.DialOption,
-	volumeId needle.VolumeId, sourceLocation string, toBeUnmountedhardIds []uint32) error {
+func unmountEcShards(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceLocation string, toBeUnmountedhardIds []uint32) error {
 
 	fmt.Printf("unmount %d.%v from %s\n", volumeId, toBeUnmountedhardIds, sourceLocation)
 
-	return operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, deleteErr := volumeServerClient.VolumeEcShardsUnmount(ctx, &volume_server_pb.VolumeEcShardsUnmountRequest{
+	return operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, deleteErr := volumeServerClient.VolumeEcShardsUnmount(context.Background(), &volume_server_pb.VolumeEcShardsUnmountRequest{
 			VolumeId: uint32(volumeId),
 			ShardIds: toBeUnmountedhardIds,
 		})
@@ -241,13 +239,12 @@ func unmountEcShards(ctx context.Context, grpcDialOption grpc.DialOption,
 	})
 }
 
-func mountEcShards(ctx context.Context, grpcDialOption grpc.DialOption,
-	collection string, volumeId needle.VolumeId, sourceLocation string, toBeMountedhardIds []uint32) error {
+func mountEcShards(grpcDialOption grpc.DialOption, collection string, volumeId needle.VolumeId, sourceLocation string, toBeMountedhardIds []uint32) error {
 
 	fmt.Printf("mount %d.%v on %s\n", volumeId, toBeMountedhardIds, sourceLocation)
 
-	return operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, mountErr := volumeServerClient.VolumeEcShardsMount(ctx, &volume_server_pb.VolumeEcShardsMountRequest{
+	return operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, mountErr := volumeServerClient.VolumeEcShardsMount(context.Background(), &volume_server_pb.VolumeEcShardsMountRequest{
 			VolumeId:   uint32(volumeId),
 			Collection: collection,
 			ShardIds:   toBeMountedhardIds,
diff --git a/weed/shell/command_ec_decode.go b/weed/shell/command_ec_decode.go
index 8a705a5ae..b69e403cb 100644
--- a/weed/shell/command_ec_decode.go
+++ b/weed/shell/command_ec_decode.go
@@ -43,25 +43,24 @@ func (c *commandEcDecode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 		return nil
 	}
 
-	ctx := context.Background()
 	vid := needle.VolumeId(*volumeId)
 
 	// collect topology information
-	topologyInfo, err := collectTopologyInfo(ctx, commandEnv)
+	topologyInfo, err := collectTopologyInfo(commandEnv)
 	if err != nil {
 		return err
 	}
 
 	// volumeId is provided
 	if vid != 0 {
-		return doEcDecode(ctx, commandEnv, topologyInfo, *collection, vid)
+		return doEcDecode(commandEnv, topologyInfo, *collection, vid)
 	}
 
 	// apply to all volumes in the collection
 	volumeIds := collectEcShardIds(topologyInfo, *collection)
 	fmt.Printf("ec encode volumes: %v\n", volumeIds)
 	for _, vid := range volumeIds {
-		if err = doEcDecode(ctx, commandEnv, topologyInfo, *collection, vid); err != nil {
+		if err = doEcDecode(commandEnv, topologyInfo, *collection, vid); err != nil {
 			return err
 		}
 	}
@@ -69,26 +68,26 @@ func (c *commandEcDecode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 	return nil
 }
 
-func doEcDecode(ctx context.Context, commandEnv *CommandEnv, topoInfo *master_pb.TopologyInfo, collection string, vid needle.VolumeId) (err error) {
+func doEcDecode(commandEnv *CommandEnv, topoInfo *master_pb.TopologyInfo, collection string, vid needle.VolumeId) (err error) {
 	// find volume location
 	nodeToEcIndexBits := collectEcNodeShardBits(topoInfo, vid)
 
 	fmt.Printf("ec volume %d shard locations: %+v\n", vid, nodeToEcIndexBits)
 
 	// collect ec shards to the server with most space
-	targetNodeLocation, err := collectEcShards(ctx, commandEnv, nodeToEcIndexBits, collection, vid)
+	targetNodeLocation, err := collectEcShards(commandEnv, nodeToEcIndexBits, collection, vid)
 	if err != nil {
 		return fmt.Errorf("collectEcShards for volume %d: %v", vid, err)
 	}
 
 	// generate a normal volume
-	err = generateNormalVolume(ctx, commandEnv.option.GrpcDialOption, needle.VolumeId(vid), collection, targetNodeLocation)
+	err = generateNormalVolume(commandEnv.option.GrpcDialOption, needle.VolumeId(vid), collection, targetNodeLocation)
 	if err != nil {
 		return fmt.Errorf("generate normal volume %d on %s: %v", vid, targetNodeLocation, err)
 	}
 
 	// delete the previous ec shards
-	err = mountVolumeAndDeleteEcShards(ctx, commandEnv.option.GrpcDialOption, collection, targetNodeLocation, nodeToEcIndexBits, vid)
+	err = mountVolumeAndDeleteEcShards(commandEnv.option.GrpcDialOption, collection, targetNodeLocation, nodeToEcIndexBits, vid)
 	if err != nil {
 		return fmt.Errorf("delete ec shards for volume %d: %v", vid, err)
 	}
@@ -96,11 +95,11 @@ func doEcDecode(ctx context.Context, commandEnv *CommandEnv, topoInfo *master_pb
 	return nil
 }
 
-func mountVolumeAndDeleteEcShards(ctx context.Context, grpcDialOption grpc.DialOption, collection, targetNodeLocation string, nodeToEcIndexBits map[string]erasure_coding.ShardBits, vid needle.VolumeId) error {
+func mountVolumeAndDeleteEcShards(grpcDialOption grpc.DialOption, collection, targetNodeLocation string, nodeToEcIndexBits map[string]erasure_coding.ShardBits, vid needle.VolumeId) error {
 
 	// mount volume
-	if err := operation.WithVolumeServerClient(targetNodeLocation, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, mountErr := volumeServerClient.VolumeMount(ctx, &volume_server_pb.VolumeMountRequest{
+	if err := operation.WithVolumeServerClient(targetNodeLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, mountErr := volumeServerClient.VolumeMount(context.Background(), &volume_server_pb.VolumeMountRequest{
 			VolumeId: uint32(vid),
 		})
 		return mountErr
@@ -111,7 +110,7 @@ func mountVolumeAndDeleteEcShards(ctx context.Context, grpcDialOption grpc.DialO
 	// unmount ec shards
 	for location, ecIndexBits := range nodeToEcIndexBits {
 		fmt.Printf("unmount ec volume %d on %s has shards: %+v\n", vid, location, ecIndexBits.ShardIds())
-		err := unmountEcShards(ctx, grpcDialOption, vid, location, ecIndexBits.ToUint32Slice())
+		err := unmountEcShards(grpcDialOption, vid, location, ecIndexBits.ToUint32Slice())
 		if err != nil {
 			return fmt.Errorf("mountVolumeAndDeleteEcShards unmount ec volume %d on %s: %v", vid, location, err)
 		}
@@ -119,7 +118,7 @@ func mountVolumeAndDeleteEcShards(ctx context.Context, grpcDialOption grpc.DialO
 	// delete ec shards
 	for location, ecIndexBits := range nodeToEcIndexBits {
 		fmt.Printf("delete ec volume %d on %s has shards: %+v\n", vid, location, ecIndexBits.ShardIds())
-		err := sourceServerDeleteEcShards(ctx, grpcDialOption, collection, vid, location, ecIndexBits.ToUint32Slice())
+		err := sourceServerDeleteEcShards(grpcDialOption, collection, vid, location, ecIndexBits.ToUint32Slice())
 		if err != nil {
 			return fmt.Errorf("mountVolumeAndDeleteEcShards delete ec volume %d on %s: %v", vid, location, err)
 		}
@@ -128,12 +127,12 @@ func mountVolumeAndDeleteEcShards(ctx context.Context, grpcDialOption grpc.DialO
 	return nil
 }
 
-func generateNormalVolume(ctx context.Context, grpcDialOption grpc.DialOption, vid needle.VolumeId, collection string, sourceVolumeServer string) error {
+func generateNormalVolume(grpcDialOption grpc.DialOption, vid needle.VolumeId, collection string, sourceVolumeServer string) error {
 
 	fmt.Printf("generateNormalVolume from ec volume %d on %s\n", vid, sourceVolumeServer)
 
-	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, genErr := volumeServerClient.VolumeEcShardsToVolume(ctx, &volume_server_pb.VolumeEcShardsToVolumeRequest{
+	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, genErr := volumeServerClient.VolumeEcShardsToVolume(context.Background(), &volume_server_pb.VolumeEcShardsToVolumeRequest{
 			VolumeId:   uint32(vid),
 			Collection: collection,
 		})
@@ -144,7 +143,7 @@ func generateNormalVolume(ctx context.Context, grpcDialOption grpc.DialOption, v
 
 }
 
-func collectEcShards(ctx context.Context, commandEnv *CommandEnv, nodeToEcIndexBits map[string]erasure_coding.ShardBits, collection string, vid needle.VolumeId) (targetNodeLocation string, err error) {
+func collectEcShards(commandEnv *CommandEnv, nodeToEcIndexBits map[string]erasure_coding.ShardBits, collection string, vid needle.VolumeId) (targetNodeLocation string, err error) {
 
 	maxShardCount := 0
 	var exisitngEcIndexBits erasure_coding.ShardBits
@@ -170,11 +169,11 @@ func collectEcShards(ctx context.Context, commandEnv *CommandEnv, nodeToEcIndexB
 			continue
 		}
 
-		err = operation.WithVolumeServerClient(targetNodeLocation, commandEnv.option.GrpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
+		err = operation.WithVolumeServerClient(targetNodeLocation, commandEnv.option.GrpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
 
 			fmt.Printf("copy %d.%v %s => %s\n", vid, needToCopyEcIndexBits.ShardIds(), loc, targetNodeLocation)
 
-			_, copyErr := volumeServerClient.VolumeEcShardsCopy(ctx, &volume_server_pb.VolumeEcShardsCopyRequest{
+			_, copyErr := volumeServerClient.VolumeEcShardsCopy(context.Background(), &volume_server_pb.VolumeEcShardsCopyRequest{
 				VolumeId:       uint32(vid),
 				Collection:     collection,
 				ShardIds:       needToCopyEcIndexBits.ToUint32Slice(),
@@ -204,11 +203,11 @@ func collectEcShards(ctx context.Context, commandEnv *CommandEnv, nodeToEcIndexB
 
 }
 
-func collectTopologyInfo(ctx context.Context, commandEnv *CommandEnv) (topoInfo *master_pb.TopologyInfo, err error) {
+func collectTopologyInfo(commandEnv *CommandEnv) (topoInfo *master_pb.TopologyInfo, err error) {
 
 	var resp *master_pb.VolumeListResponse
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
diff --git a/weed/shell/command_ec_encode.go b/weed/shell/command_ec_encode.go
index 587b59388..e22691c00 100644
--- a/weed/shell/command_ec_encode.go
+++ b/weed/shell/command_ec_encode.go
@@ -63,22 +63,21 @@ func (c *commandEcEncode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 		return nil
 	}
 
-	ctx := context.Background()
 	vid := needle.VolumeId(*volumeId)
 
 	// volumeId is provided
 	if vid != 0 {
-		return doEcEncode(ctx, commandEnv, *collection, vid)
+		return doEcEncode(commandEnv, *collection, vid)
 	}
 
 	// apply to all volumes in the collection
-	volumeIds, err := collectVolumeIdsForEcEncode(ctx, commandEnv, *collection, *fullPercentage, *quietPeriod)
+	volumeIds, err := collectVolumeIdsForEcEncode(commandEnv, *collection, *fullPercentage, *quietPeriod)
 	if err != nil {
 		return err
 	}
 	fmt.Printf("ec encode volumes: %v\n", volumeIds)
 	for _, vid := range volumeIds {
-		if err = doEcEncode(ctx, commandEnv, *collection, vid); err != nil {
+		if err = doEcEncode(commandEnv, *collection, vid); err != nil {
 			return err
 		}
 	}
@@ -86,7 +85,7 @@ func (c *commandEcEncode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 	return nil
 }
 
-func doEcEncode(ctx context.Context, commandEnv *CommandEnv, collection string, vid needle.VolumeId) (err error) {
+func doEcEncode(commandEnv *CommandEnv, collection string, vid needle.VolumeId) (err error) {
 	// find volume location
 	locations, found := commandEnv.MasterClient.GetLocations(uint32(vid))
 	if !found {
@@ -96,19 +95,19 @@ func doEcEncode(ctx context.Context, commandEnv *CommandEnv, collection string,
 	// fmt.Printf("found ec %d shards on %v\n", vid, locations)
 
 	// mark the volume as readonly
-	err = markVolumeReadonly(ctx, commandEnv.option.GrpcDialOption, needle.VolumeId(vid), locations)
+	err = markVolumeReadonly(commandEnv.option.GrpcDialOption, needle.VolumeId(vid), locations)
 	if err != nil {
 		return fmt.Errorf("mark volume %d as readonly on %s: %v", vid, locations[0].Url, err)
 	}
 
 	// generate ec shards
-	err = generateEcShards(ctx, commandEnv.option.GrpcDialOption, needle.VolumeId(vid), collection, locations[0].Url)
+	err = generateEcShards(commandEnv.option.GrpcDialOption, needle.VolumeId(vid), collection, locations[0].Url)
 	if err != nil {
 		return fmt.Errorf("generate ec shards for volume %d on %s: %v", vid, locations[0].Url, err)
 	}
 
 	// balance the ec shards to current cluster
-	err = spreadEcShards(ctx, commandEnv, vid, collection, locations)
+	err = spreadEcShards(context.Background(), commandEnv, vid, collection, locations)
 	if err != nil {
 		return fmt.Errorf("spread ec shards for volume %d from %s: %v", vid, locations[0].Url, err)
 	}
@@ -116,12 +115,12 @@ func doEcEncode(ctx context.Context, commandEnv *CommandEnv, collection string,
 	return nil
 }
 
-func markVolumeReadonly(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, locations []wdclient.Location) error {
+func markVolumeReadonly(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, locations []wdclient.Location) error {
 
 	for _, location := range locations {
 
-		err := operation.WithVolumeServerClient(location.Url, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-			_, markErr := volumeServerClient.VolumeMarkReadonly(ctx, &volume_server_pb.VolumeMarkReadonlyRequest{
+		err := operation.WithVolumeServerClient(location.Url, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+			_, markErr := volumeServerClient.VolumeMarkReadonly(context.Background(), &volume_server_pb.VolumeMarkReadonlyRequest{
 				VolumeId: uint32(volumeId),
 			})
 			return markErr
@@ -136,10 +135,10 @@ func markVolumeReadonly(ctx context.Context, grpcDialOption grpc.DialOption, vol
 	return nil
 }
 
-func generateEcShards(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, collection string, sourceVolumeServer string) error {
+func generateEcShards(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, collection string, sourceVolumeServer string) error {
 
-	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, genErr := volumeServerClient.VolumeEcShardsGenerate(ctx, &volume_server_pb.VolumeEcShardsGenerateRequest{
+	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, genErr := volumeServerClient.VolumeEcShardsGenerate(context.Background(), &volume_server_pb.VolumeEcShardsGenerateRequest{
 			VolumeId:   uint32(volumeId),
 			Collection: collection,
 		})
@@ -152,7 +151,7 @@ func generateEcShards(ctx context.Context, grpcDialOption grpc.DialOption, volum
 
 func spreadEcShards(ctx context.Context, commandEnv *CommandEnv, volumeId needle.VolumeId, collection string, existingLocations []wdclient.Location) (err error) {
 
-	allEcNodes, totalFreeEcSlots, err := collectEcNodes(ctx, commandEnv, "")
+	allEcNodes, totalFreeEcSlots, err := collectEcNodes(commandEnv, "")
 	if err != nil {
 		return err
 	}
@@ -169,26 +168,26 @@ func spreadEcShards(ctx context.Context, commandEnv *CommandEnv, volumeId needle
 	allocatedEcIds := balancedEcDistribution(allocatedDataNodes)
 
 	// ask the data nodes to copy from the source volume server
-	copiedShardIds, err := parallelCopyEcShardsFromSource(ctx, commandEnv.option.GrpcDialOption, allocatedDataNodes, allocatedEcIds, volumeId, collection, existingLocations[0])
+	copiedShardIds, err := parallelCopyEcShardsFromSource(commandEnv.option.GrpcDialOption, allocatedDataNodes, allocatedEcIds, volumeId, collection, existingLocations[0])
 	if err != nil {
 		return err
 	}
 
 	// unmount the to be deleted shards
-	err = unmountEcShards(ctx, commandEnv.option.GrpcDialOption, volumeId, existingLocations[0].Url, copiedShardIds)
+	err = unmountEcShards(commandEnv.option.GrpcDialOption, volumeId, existingLocations[0].Url, copiedShardIds)
 	if err != nil {
 		return err
 	}
 
 	// ask the source volume server to clean up copied ec shards
-	err = sourceServerDeleteEcShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, existingLocations[0].Url, copiedShardIds)
+	err = sourceServerDeleteEcShards(commandEnv.option.GrpcDialOption, collection, volumeId, existingLocations[0].Url, copiedShardIds)
 	if err != nil {
 		return fmt.Errorf("source delete copied ecShards %s %d.%v: %v", existingLocations[0].Url, volumeId, copiedShardIds, err)
 	}
 
 	// ask the source volume server to delete the original volume
 	for _, location := range existingLocations {
-		err = deleteVolume(ctx, commandEnv.option.GrpcDialOption, volumeId, location.Url)
+		err = deleteVolume(commandEnv.option.GrpcDialOption, volumeId, location.Url)
 		if err != nil {
 			return fmt.Errorf("deleteVolume %s volume %d: %v", location.Url, volumeId, err)
 		}
@@ -198,9 +197,7 @@ func spreadEcShards(ctx context.Context, commandEnv *CommandEnv, volumeId needle
 
 }
 
-func parallelCopyEcShardsFromSource(ctx context.Context, grpcDialOption grpc.DialOption,
-	targetServers []*EcNode, allocatedEcIds [][]uint32,
-	volumeId needle.VolumeId, collection string, existingLocation wdclient.Location) (actuallyCopied []uint32, err error) {
+func parallelCopyEcShardsFromSource(grpcDialOption grpc.DialOption, targetServers []*EcNode, allocatedEcIds [][]uint32, volumeId needle.VolumeId, collection string, existingLocation wdclient.Location) (actuallyCopied []uint32, err error) {
 
 	// parallelize
 	shardIdChan := make(chan []uint32, len(targetServers))
@@ -213,7 +210,7 @@ func parallelCopyEcShardsFromSource(ctx context.Context, grpcDialOption grpc.Dia
 		wg.Add(1)
 		go func(server *EcNode, allocatedEcShardIds []uint32) {
 			defer wg.Done()
-			copiedShardIds, copyErr := oneServerCopyAndMountEcShardsFromSource(ctx, grpcDialOption, server,
+			copiedShardIds, copyErr := oneServerCopyAndMountEcShardsFromSource(grpcDialOption, server,
 				allocatedEcShardIds, volumeId, collection, existingLocation.Url)
 			if copyErr != nil {
 				err = copyErr
@@ -255,11 +252,11 @@ func balancedEcDistribution(servers []*EcNode) (allocated [][]uint32) {
 	return allocated
 }
 
-func collectVolumeIdsForEcEncode(ctx context.Context, commandEnv *CommandEnv, selectedCollection string, fullPercentage float64, quietPeriod time.Duration) (vids []needle.VolumeId, err error) {
+func collectVolumeIdsForEcEncode(commandEnv *CommandEnv, selectedCollection string, fullPercentage float64, quietPeriod time.Duration) (vids []needle.VolumeId, err error) {
 
 	var resp *master_pb.VolumeListResponse
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
diff --git a/weed/shell/command_ec_rebuild.go b/weed/shell/command_ec_rebuild.go
index 600a8cb45..d9d943e6d 100644
--- a/weed/shell/command_ec_rebuild.go
+++ b/weed/shell/command_ec_rebuild.go
@@ -64,7 +64,7 @@ func (c *commandEcRebuild) Do(args []string, commandEnv *CommandEnv, writer io.W
 	}
 
 	// collect all ec nodes
-	allEcNodes, _, err := collectEcNodes(context.Background(), commandEnv, "")
+	allEcNodes, _, err := collectEcNodes(commandEnv, "")
 	if err != nil {
 		return err
 	}
@@ -92,8 +92,6 @@ func (c *commandEcRebuild) Do(args []string, commandEnv *CommandEnv, writer io.W
 
 func rebuildEcVolumes(commandEnv *CommandEnv, allEcNodes []*EcNode, collection string, writer io.Writer, applyChanges bool) error {
 
-	ctx := context.Background()
-
 	fmt.Printf("rebuildEcVolumes %s\n", collection)
 
 	// collect vid => each shard locations, similar to ecShardMap in topology.go
@@ -117,7 +115,7 @@ func rebuildEcVolumes(commandEnv *CommandEnv, allEcNodes []*EcNode, collection s
 			return fmt.Errorf("disk space is not enough")
 		}
 
-		if err := rebuildOneEcVolume(ctx, commandEnv, allEcNodes[0], collection, vid, locations, writer, applyChanges); err != nil {
+		if err := rebuildOneEcVolume(commandEnv, allEcNodes[0], collection, vid, locations, writer, applyChanges); err != nil {
 			return err
 		}
 	}
@@ -125,13 +123,13 @@ func rebuildEcVolumes(commandEnv *CommandEnv, allEcNodes []*EcNode, collection s
 	return nil
 }
 
-func rebuildOneEcVolume(ctx context.Context, commandEnv *CommandEnv, rebuilder *EcNode, collection string, volumeId needle.VolumeId, locations EcShardLocations, writer io.Writer, applyChanges bool) error {
+func rebuildOneEcVolume(commandEnv *CommandEnv, rebuilder *EcNode, collection string, volumeId needle.VolumeId, locations EcShardLocations, writer io.Writer, applyChanges bool) error {
 
 	fmt.Printf("rebuildOneEcVolume %s %d\n", collection, volumeId)
 
 	// collect shard files to rebuilder local disk
 	var generatedShardIds []uint32
-	copiedShardIds, _, err := prepareDataToRecover(ctx, commandEnv, rebuilder, collection, volumeId, locations, writer, applyChanges)
+	copiedShardIds, _, err := prepareDataToRecover(commandEnv, rebuilder, collection, volumeId, locations, writer, applyChanges)
 	if err != nil {
 		return err
 	}
@@ -139,7 +137,7 @@ func rebuildOneEcVolume(ctx context.Context, commandEnv *CommandEnv, rebuilder *
 		// clean up working files
 
 		// ask the rebuilder to delete the copied shards
-		err = sourceServerDeleteEcShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id, copiedShardIds)
+		err = sourceServerDeleteEcShards(commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id, copiedShardIds)
 		if err != nil {
 			fmt.Fprintf(writer, "%s delete copied ec shards %s %d.%v\n", rebuilder.info.Id, collection, volumeId, copiedShardIds)
 		}
@@ -151,13 +149,13 @@ func rebuildOneEcVolume(ctx context.Context, commandEnv *CommandEnv, rebuilder *
 	}
 
 	// generate ec shards, and maybe ecx file
-	generatedShardIds, err = generateMissingShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id)
+	generatedShardIds, err = generateMissingShards(commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id)
 	if err != nil {
 		return err
 	}
 
 	// mount the generated shards
-	err = mountEcShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id, generatedShardIds)
+	err = mountEcShards(commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id, generatedShardIds)
 	if err != nil {
 		return err
 	}
@@ -167,11 +165,10 @@ func rebuildOneEcVolume(ctx context.Context, commandEnv *CommandEnv, rebuilder *
 	return nil
 }
 
-func generateMissingShards(ctx context.Context, grpcDialOption grpc.DialOption,
-	collection string, volumeId needle.VolumeId, sourceLocation string) (rebuiltShardIds []uint32, err error) {
+func generateMissingShards(grpcDialOption grpc.DialOption, collection string, volumeId needle.VolumeId, sourceLocation string) (rebuiltShardIds []uint32, err error) {
 
-	err = operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		resp, rebultErr := volumeServerClient.VolumeEcShardsRebuild(ctx, &volume_server_pb.VolumeEcShardsRebuildRequest{
+	err = operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		resp, rebultErr := volumeServerClient.VolumeEcShardsRebuild(context.Background(), &volume_server_pb.VolumeEcShardsRebuildRequest{
 			VolumeId:   uint32(volumeId),
 			Collection: collection,
 		})
@@ -183,7 +180,7 @@ func generateMissingShards(ctx context.Context, grpcDialOption grpc.DialOption,
 	return
 }
 
-func prepareDataToRecover(ctx context.Context, commandEnv *CommandEnv, rebuilder *EcNode, collection string, volumeId needle.VolumeId, locations EcShardLocations, writer io.Writer, applyBalancing bool) (copiedShardIds []uint32, localShardIds []uint32, err error) {
+func prepareDataToRecover(commandEnv *CommandEnv, rebuilder *EcNode, collection string, volumeId needle.VolumeId, locations EcShardLocations, writer io.Writer, applyBalancing bool) (copiedShardIds []uint32, localShardIds []uint32, err error) {
 
 	needEcxFile := true
 	var localShardBits erasure_coding.ShardBits
@@ -209,8 +206,8 @@ func prepareDataToRecover(ctx context.Context, commandEnv *CommandEnv, rebuilder
 
 		var copyErr error
 		if applyBalancing {
-			copyErr = operation.WithVolumeServerClient(rebuilder.info.Id, commandEnv.option.GrpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-				_, copyErr := volumeServerClient.VolumeEcShardsCopy(ctx, &volume_server_pb.VolumeEcShardsCopyRequest{
+			copyErr = operation.WithVolumeServerClient(rebuilder.info.Id, commandEnv.option.GrpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+				_, copyErr := volumeServerClient.VolumeEcShardsCopy(context.Background(), &volume_server_pb.VolumeEcShardsCopyRequest{
 					VolumeId:       uint32(volumeId),
 					Collection:     collection,
 					ShardIds:       []uint32{uint32(shardId)},
diff --git a/weed/shell/command_ec_test.go b/weed/shell/command_ec_test.go
index c233d25d0..ddd52303c 100644
--- a/weed/shell/command_ec_test.go
+++ b/weed/shell/command_ec_test.go
@@ -121,7 +121,7 @@ func TestCommandEcBalanceVolumeEvenButRackUneven(t *testing.T) {
 
 	racks := collectRacks(allEcNodes)
 	balanceEcVolumes(nil, "c1", allEcNodes, racks, false)
-	balanceEcRacks(context.Background(), nil, racks, false)
+	balanceEcRacks(nil, racks, false)
 }
 
 func newEcNode(dc string, rack string, dataNodeId string, freeEcSlot int) *EcNode {
diff --git a/weed/shell/command_fs_cat.go b/weed/shell/command_fs_cat.go
index 06c8232c9..8364e0de1 100644
--- a/weed/shell/command_fs_cat.go
+++ b/weed/shell/command_fs_cat.go
@@ -38,21 +38,19 @@ func (c *commandFsCat) Do(args []string, commandEnv *CommandEnv, writer io.Write
 		return err
 	}
 
-	ctx := context.Background()
-
-	if commandEnv.isDirectory(ctx, filerServer, filerPort, path) {
+	if commandEnv.isDirectory(filerServer, filerPort, path) {
 		return fmt.Errorf("%s is a directory", path)
 	}
 
 	dir, name := filer2.FullPath(path).DirAndName()
 
-	return commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Name:      name,
 			Directory: dir,
 		}
-		respLookupEntry, err := client.LookupDirectoryEntry(ctx, request)
+		respLookupEntry, err := client.LookupDirectoryEntry(context.Background(), request)
 		if err != nil {
 			return err
 		}
diff --git a/weed/shell/command_fs_cd.go b/weed/shell/command_fs_cd.go
index 408ec86c8..df42cd516 100644
--- a/weed/shell/command_fs_cd.go
+++ b/weed/shell/command_fs_cd.go
@@ -1,7 +1,6 @@
 package shell
 
 import (
-	"context"
 	"io"
 )
 
@@ -45,9 +44,7 @@ func (c *commandFsCd) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 		return nil
 	}
 
-	ctx := context.Background()
-
-	err = commandEnv.checkDirectory(ctx, filerServer, filerPort, path)
+	err = commandEnv.checkDirectory(filerServer, filerPort, path)
 
 	if err == nil {
 		commandEnv.option.FilerHost = filerServer
diff --git a/weed/shell/command_fs_du.go b/weed/shell/command_fs_du.go
index d6ea51d0c..a1e21bfa6 100644
--- a/weed/shell/command_fs_du.go
+++ b/weed/shell/command_fs_du.go
@@ -1,7 +1,6 @@
 package shell
 
 import (
-	"context"
 	"fmt"
 	"io"
 
@@ -39,15 +38,13 @@ func (c *commandFsDu) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 		return err
 	}
 
-	ctx := context.Background()
-
-	if commandEnv.isDirectory(ctx, filerServer, filerPort, path) {
+	if commandEnv.isDirectory(filerServer, filerPort, path) {
 		path = path + "/"
 	}
 
 	var blockCount, byteCount uint64
 	dir, name := filer2.FullPath(path).DirAndName()
-	blockCount, byteCount, err = duTraverseDirectory(ctx, writer, commandEnv.getFilerClient(filerServer, filerPort), dir, name)
+	blockCount, byteCount, err = duTraverseDirectory(writer, commandEnv.getFilerClient(filerServer, filerPort), dir, name)
 
 	if name == "" && err == nil {
 		fmt.Fprintf(writer, "block:%4d\tbyte:%10d\t%s\n", blockCount, byteCount, dir)
@@ -57,15 +54,15 @@ func (c *commandFsDu) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 
 }
 
-func duTraverseDirectory(ctx context.Context, writer io.Writer, filerClient filer2.FilerClient, dir, name string) (blockCount uint64, byteCount uint64, err error) {
+func duTraverseDirectory(writer io.Writer, filerClient filer2.FilerClient, dir, name string) (blockCount, byteCount uint64, err error) {
 
-	err = filer2.ReadDirAllEntries(ctx, filerClient, filer2.FullPath(dir), name, func(entry *filer_pb.Entry, isLast bool) {
+	err = filer2.ReadDirAllEntries(filerClient, filer2.FullPath(dir), name, func(entry *filer_pb.Entry, isLast bool) {
 		if entry.IsDirectory {
 			subDir := fmt.Sprintf("%s/%s", dir, entry.Name)
 			if dir == "/" {
 				subDir = "/" + entry.Name
 			}
-			numBlock, numByte, err := duTraverseDirectory(ctx, writer, filerClient, subDir, "")
+			numBlock, numByte, err := duTraverseDirectory(writer, filerClient, subDir, "")
 			if err == nil {
 				blockCount += numBlock
 				byteCount += numByte
@@ -82,12 +79,12 @@ func duTraverseDirectory(ctx context.Context, writer io.Writer, filerClient file
 	return
 }
 
-func (env *CommandEnv) withFilerClient(ctx context.Context, filerServer string, filerPort int64, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error {
+func (env *CommandEnv) withFilerClient(filerServer string, filerPort int64, fn func(filer_pb.SeaweedFilerClient) error) error {
 
 	filerGrpcAddress := fmt.Sprintf("%s:%d", filerServer, filerPort+10000)
-	return util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := filer_pb.NewSeaweedFilerClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, filerGrpcAddress, env.option.GrpcDialOption)
 
 }
@@ -105,6 +102,6 @@ func (env *CommandEnv) getFilerClient(filerServer string, filerPort int64) *comm
 		filerPort:   filerPort,
 	}
 }
-func (c *commandFilerClient) WithFilerClient(ctx context.Context, fn func(context.Context, filer_pb.SeaweedFilerClient) error) error {
-	return c.env.withFilerClient(ctx, c.filerServer, c.filerPort, fn)
+func (c *commandFilerClient) WithFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
+	return c.env.withFilerClient(c.filerServer, c.filerPort, fn)
 }
diff --git a/weed/shell/command_fs_ls.go b/weed/shell/command_fs_ls.go
index 0c63f71fa..69ebe1b30 100644
--- a/weed/shell/command_fs_ls.go
+++ b/weed/shell/command_fs_ls.go
@@ -1,7 +1,6 @@
 package shell
 
 import (
-	"context"
 	"fmt"
 	"io"
 	"os"
@@ -60,16 +59,14 @@ func (c *commandFsLs) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 		return err
 	}
 
-	ctx := context.Background()
-
-	if commandEnv.isDirectory(ctx, filerServer, filerPort, path) {
+	if commandEnv.isDirectory(filerServer, filerPort, path) {
 		path = path + "/"
 	}
 
 	dir, name := filer2.FullPath(path).DirAndName()
 	entryCount := 0
 
-	err = filer2.ReadDirAllEntries(ctx, commandEnv.getFilerClient(filerServer, filerPort), filer2.FullPath(dir), name, func(entry *filer_pb.Entry, isLast bool) {
+	err = filer2.ReadDirAllEntries(commandEnv.getFilerClient(filerServer, filerPort), filer2.FullPath(dir), name, func(entry *filer_pb.Entry, isLast bool) {
 
 		if !showHidden && strings.HasPrefix(entry.Name, ".") {
 			return
diff --git a/weed/shell/command_fs_meta_cat.go b/weed/shell/command_fs_meta_cat.go
index ec9a495f2..ec5a093df 100644
--- a/weed/shell/command_fs_meta_cat.go
+++ b/weed/shell/command_fs_meta_cat.go
@@ -41,17 +41,15 @@ func (c *commandFsMetaCat) Do(args []string, commandEnv *CommandEnv, writer io.W
 		return err
 	}
 
-	ctx := context.Background()
-
 	dir, name := filer2.FullPath(path).DirAndName()
 
-	return commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.LookupDirectoryEntryRequest{
 			Name:      name,
 			Directory: dir,
 		}
-		respLookupEntry, err := client.LookupDirectoryEntry(ctx, request)
+		respLookupEntry, err := client.LookupDirectoryEntry(context.Background(), request)
 		if err != nil {
 			return err
 		}
diff --git a/weed/shell/command_fs_meta_load.go b/weed/shell/command_fs_meta_load.go
index 8f2ef95e3..ed92d8011 100644
--- a/weed/shell/command_fs_meta_load.go
+++ b/weed/shell/command_fs_meta_load.go
@@ -1,15 +1,15 @@
 package shell
 
 import (
-	"context"
 	"fmt"
 	"io"
 	"os"
 
+	"github.com/golang/protobuf/proto"
+
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"github.com/golang/protobuf/proto"
 )
 
 func init() {
@@ -53,9 +53,7 @@ func (c *commandFsMetaLoad) Do(args []string, commandEnv *CommandEnv, writer io.
 
 	var dirCount, fileCount uint64
 
-	ctx := context.Background()
-
-	err = commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	err = commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
 		sizeBuf := make([]byte, 4)
 
@@ -80,7 +78,7 @@ func (c *commandFsMetaLoad) Do(args []string, commandEnv *CommandEnv, writer io.
 				return err
 			}
 
-			if err := filer_pb.CreateEntry(ctx, client, &filer_pb.CreateEntryRequest{
+			if err := filer_pb.CreateEntry(client, &filer_pb.CreateEntryRequest{
 				Directory: fullEntry.Dir,
 				Entry:     fullEntry.Entry,
 			}); err != nil {
diff --git a/weed/shell/command_fs_meta_save.go b/weed/shell/command_fs_meta_save.go
index 178c826d5..7112c7526 100644
--- a/weed/shell/command_fs_meta_save.go
+++ b/weed/shell/command_fs_meta_save.go
@@ -168,7 +168,7 @@ func processOneDirectory(ctx context.Context, writer io.Writer, filerClient file
 	parentPath filer2.FullPath, queue *util.Queue, jobQueueWg *sync.WaitGroup,
 	fn func(parentPath filer2.FullPath, entry *filer_pb.Entry)) (err error) {
 
-	return filer2.ReadDirAllEntries(ctx, filerClient, parentPath, "", func(entry *filer_pb.Entry, isLast bool) {
+	return filer2.ReadDirAllEntries(filerClient, parentPath, "", func(entry *filer_pb.Entry, isLast bool) {
 
 		fn(parentPath, entry)
 
diff --git a/weed/shell/command_fs_mv.go b/weed/shell/command_fs_mv.go
index b9301ad3c..78f797f6c 100644
--- a/weed/shell/command_fs_mv.go
+++ b/weed/shell/command_fs_mv.go
@@ -47,20 +47,18 @@ func (c *commandFsMv) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 		return err
 	}
 
-	ctx := context.Background()
-
 	sourceDir, sourceName := filer2.FullPath(sourcePath).DirAndName()
 
 	destinationDir, destinationName := filer2.FullPath(destinationPath).DirAndName()
 
-	return commandEnv.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return commandEnv.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
 		// collect destination entry info
 		destinationRequest := &filer_pb.LookupDirectoryEntryRequest{
 			Name:      destinationDir,
 			Directory: destinationName,
 		}
-		respDestinationLookupEntry, err := client.LookupDirectoryEntry(ctx, destinationRequest)
+		respDestinationLookupEntry, err := client.LookupDirectoryEntry(context.Background(), destinationRequest)
 
 		var targetDir, targetName string
 
@@ -82,7 +80,7 @@ func (c *commandFsMv) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 			NewName:      targetName,
 		}
 
-		_, err = client.AtomicRenameEntry(ctx, request)
+		_, err = client.AtomicRenameEntry(context.Background(), request)
 
 		fmt.Fprintf(writer, "move: %s => %s\n", sourcePath, filer2.NewFullPath(targetDir, targetName))
 
diff --git a/weed/shell/command_fs_tree.go b/weed/shell/command_fs_tree.go
index 8660030e3..fb2583240 100644
--- a/weed/shell/command_fs_tree.go
+++ b/weed/shell/command_fs_tree.go
@@ -53,7 +53,7 @@ func treeTraverseDirectory(ctx context.Context, writer io.Writer, filerClient fi
 
 	prefix.addMarker(level)
 
-	err = filer2.ReadDirAllEntries(ctx, filerClient, dir, name, func(entry *filer_pb.Entry, isLast bool) {
+	err = filer2.ReadDirAllEntries(filerClient, dir, name, func(entry *filer_pb.Entry, isLast bool) {
 		if level < 0 && name != "" {
 			if entry.Name != name {
 				return
diff --git a/weed/shell/command_volume_balance.go b/weed/shell/command_volume_balance.go
index 488beb998..349f52f1c 100644
--- a/weed/shell/command_volume_balance.go
+++ b/weed/shell/command_volume_balance.go
@@ -69,9 +69,8 @@ func (c *commandVolumeBalance) Do(args []string, commandEnv *CommandEnv, writer
 	}
 
 	var resp *master_pb.VolumeListResponse
-	ctx := context.Background()
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
@@ -239,8 +238,7 @@ func moveVolume(commandEnv *CommandEnv, v *master_pb.VolumeInformationMessage, f
 	}
 	fmt.Fprintf(os.Stdout, "moving volume %s%d %s => %s\n", collectionPrefix, v.Id, fullNode.info.Id, emptyNode.info.Id)
 	if applyBalancing {
-		ctx := context.Background()
-		return LiveMoveVolume(ctx, commandEnv.option.GrpcDialOption, needle.VolumeId(v.Id), fullNode.info.Id, emptyNode.info.Id, 5*time.Second)
+		return LiveMoveVolume(commandEnv.option.GrpcDialOption, needle.VolumeId(v.Id), fullNode.info.Id, emptyNode.info.Id, 5*time.Second)
 	}
 	return nil
 }
diff --git a/weed/shell/command_volume_configure_replication.go b/weed/shell/command_volume_configure_replication.go
index 6000d0de0..133ec62c6 100644
--- a/weed/shell/command_volume_configure_replication.go
+++ b/weed/shell/command_volume_configure_replication.go
@@ -53,9 +53,8 @@ func (c *commandVolumeConfigureReplication) Do(args []string, commandEnv *Comman
 	replicaPlacementInt32 := uint32(replicaPlacement.Byte())
 
 	var resp *master_pb.VolumeListResponse
-	ctx := context.Background()
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
@@ -81,8 +80,8 @@ func (c *commandVolumeConfigureReplication) Do(args []string, commandEnv *Comman
 	}
 
 	for _, dst := range allLocations {
-		err := operation.WithVolumeServerClient(dst.dataNode.Id, commandEnv.option.GrpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-			resp, configureErr := volumeServerClient.VolumeConfigure(ctx, &volume_server_pb.VolumeConfigureRequest{
+		err := operation.WithVolumeServerClient(dst.dataNode.Id, commandEnv.option.GrpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+			resp, configureErr := volumeServerClient.VolumeConfigure(context.Background(), &volume_server_pb.VolumeConfigureRequest{
 				VolumeId:    uint32(vid),
 				Replication: replicaPlacement.String(),
 			})
diff --git a/weed/shell/command_volume_copy.go b/weed/shell/command_volume_copy.go
index 1c83ba655..aecc071ad 100644
--- a/weed/shell/command_volume_copy.go
+++ b/weed/shell/command_volume_copy.go
@@ -1,7 +1,6 @@
 package shell
 
 import (
-	"context"
 	"fmt"
 	"io"
 
@@ -47,7 +46,6 @@ func (c *commandVolumeCopy) Do(args []string, commandEnv *CommandEnv, writer io.
 		return fmt.Errorf("source and target volume servers are the same!")
 	}
 
-	ctx := context.Background()
-	_, err = copyVolume(ctx, commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer)
+	_, err = copyVolume(commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer)
 	return
 }
diff --git a/weed/shell/command_volume_delete.go b/weed/shell/command_volume_delete.go
index 17d27ea3a..5869b1621 100644
--- a/weed/shell/command_volume_delete.go
+++ b/weed/shell/command_volume_delete.go
@@ -1,7 +1,6 @@
 package shell
 
 import (
-	"context"
 	"fmt"
 	"io"
 
@@ -42,7 +41,6 @@ func (c *commandVolumeDelete) Do(args []string, commandEnv *CommandEnv, writer i
 		return fmt.Errorf("wrong volume id format %s: %v", volumeId, err)
 	}
 
-	ctx := context.Background()
-	return deleteVolume(ctx, commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer)
+	return deleteVolume(commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer)
 
 }
diff --git a/weed/shell/command_volume_fix_replication.go b/weed/shell/command_volume_fix_replication.go
index 7a1a77cbe..210f4819d 100644
--- a/weed/shell/command_volume_fix_replication.go
+++ b/weed/shell/command_volume_fix_replication.go
@@ -50,9 +50,8 @@ func (c *commandVolumeFixReplication) Do(args []string, commandEnv *CommandEnv,
 	}
 
 	var resp *master_pb.VolumeListResponse
-	ctx := context.Background()
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
@@ -113,8 +112,8 @@ func (c *commandVolumeFixReplication) Do(args []string, commandEnv *CommandEnv,
 					break
 				}
 
-				err := operation.WithVolumeServerClient(dst.dataNode.Id, commandEnv.option.GrpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-					_, replicateErr := volumeServerClient.VolumeCopy(ctx, &volume_server_pb.VolumeCopyRequest{
+				err := operation.WithVolumeServerClient(dst.dataNode.Id, commandEnv.option.GrpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+					_, replicateErr := volumeServerClient.VolumeCopy(context.Background(), &volume_server_pb.VolumeCopyRequest{
 						VolumeId:       volumeInfo.Id,
 						SourceDataNode: sourceNode.dataNode.Id,
 					})
diff --git a/weed/shell/command_volume_list.go b/weed/shell/command_volume_list.go
index c6c79d150..c5a9388fa 100644
--- a/weed/shell/command_volume_list.go
+++ b/weed/shell/command_volume_list.go
@@ -32,9 +32,8 @@ func (c *commandVolumeList) Help() string {
 func (c *commandVolumeList) Do(args []string, commandEnv *CommandEnv, writer io.Writer) (err error) {
 
 	var resp *master_pb.VolumeListResponse
-	ctx := context.Background()
-	err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
-		resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
+	err = commandEnv.MasterClient.WithClient(func(client master_pb.SeaweedClient) error {
+		resp, err = client.VolumeList(context.Background(), &master_pb.VolumeListRequest{})
 		return err
 	})
 	if err != nil {
diff --git a/weed/shell/command_volume_mount.go b/weed/shell/command_volume_mount.go
index 21bc342b4..cffc7136b 100644
--- a/weed/shell/command_volume_mount.go
+++ b/weed/shell/command_volume_mount.go
@@ -45,14 +45,13 @@ func (c *commandVolumeMount) Do(args []string, commandEnv *CommandEnv, writer io
 		return fmt.Errorf("wrong volume id format %s: %v", volumeId, err)
 	}
 
-	ctx := context.Background()
-	return mountVolume(ctx, commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer)
+	return mountVolume(commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer)
 
 }
 
-func mountVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
-	return operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, mountErr := volumeServerClient.VolumeMount(ctx, &volume_server_pb.VolumeMountRequest{
+func mountVolume(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
+	return operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, mountErr := volumeServerClient.VolumeMount(context.Background(), &volume_server_pb.VolumeMountRequest{
 			VolumeId: uint32(volumeId),
 		})
 		return mountErr
diff --git a/weed/shell/command_volume_move.go b/weed/shell/command_volume_move.go
index 2e39c0600..c25b953a5 100644
--- a/weed/shell/command_volume_move.go
+++ b/weed/shell/command_volume_move.go
@@ -59,26 +59,25 @@ func (c *commandVolumeMove) Do(args []string, commandEnv *CommandEnv, writer io.
 		return fmt.Errorf("source and target volume servers are the same!")
 	}
 
-	ctx := context.Background()
-	return LiveMoveVolume(ctx, commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer, 5*time.Second)
+	return LiveMoveVolume(commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer, 5*time.Second)
 }
 
 // LiveMoveVolume moves one volume from one source volume server to one target volume server, with idleTimeout to drain the incoming requests.
-func LiveMoveVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string, idleTimeout time.Duration) (err error) {
+func LiveMoveVolume(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string, idleTimeout time.Duration) (err error) {
 
 	log.Printf("copying volume %d from %s to %s", volumeId, sourceVolumeServer, targetVolumeServer)
-	lastAppendAtNs, err := copyVolume(ctx, grpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer)
+	lastAppendAtNs, err := copyVolume(grpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer)
 	if err != nil {
 		return fmt.Errorf("copy volume %d from %s to %s: %v", volumeId, sourceVolumeServer, targetVolumeServer, err)
 	}
 
 	log.Printf("tailing volume %d from %s to %s", volumeId, sourceVolumeServer, targetVolumeServer)
-	if err = tailVolume(ctx, grpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer, lastAppendAtNs, idleTimeout); err != nil {
+	if err = tailVolume(grpcDialOption, volumeId, sourceVolumeServer, targetVolumeServer, lastAppendAtNs, idleTimeout); err != nil {
 		return fmt.Errorf("tail volume %d from %s to %s: %v", volumeId, sourceVolumeServer, targetVolumeServer, err)
 	}
 
 	log.Printf("deleting volume %d from %s", volumeId, sourceVolumeServer)
-	if err = deleteVolume(ctx, grpcDialOption, volumeId, sourceVolumeServer); err != nil {
+	if err = deleteVolume(grpcDialOption, volumeId, sourceVolumeServer); err != nil {
 		return fmt.Errorf("delete volume %d from %s: %v", volumeId, sourceVolumeServer, err)
 	}
 
@@ -86,10 +85,10 @@ func LiveMoveVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeI
 	return nil
 }
 
-func copyVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string) (lastAppendAtNs uint64, err error) {
+func copyVolume(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string) (lastAppendAtNs uint64, err error) {
 
-	err = operation.WithVolumeServerClient(targetVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		resp, replicateErr := volumeServerClient.VolumeCopy(ctx, &volume_server_pb.VolumeCopyRequest{
+	err = operation.WithVolumeServerClient(targetVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		resp, replicateErr := volumeServerClient.VolumeCopy(context.Background(), &volume_server_pb.VolumeCopyRequest{
 			VolumeId:       uint32(volumeId),
 			SourceDataNode: sourceVolumeServer,
 		})
@@ -102,10 +101,10 @@ func copyVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId ne
 	return
 }
 
-func tailVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string, lastAppendAtNs uint64, idleTimeout time.Duration) (err error) {
+func tailVolume(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string, lastAppendAtNs uint64, idleTimeout time.Duration) (err error) {
 
-	return operation.WithVolumeServerClient(targetVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, replicateErr := volumeServerClient.VolumeTailReceiver(ctx, &volume_server_pb.VolumeTailReceiverRequest{
+	return operation.WithVolumeServerClient(targetVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, replicateErr := volumeServerClient.VolumeTailReceiver(context.Background(), &volume_server_pb.VolumeTailReceiverRequest{
 			VolumeId:           uint32(volumeId),
 			SinceNs:            lastAppendAtNs,
 			IdleTimeoutSeconds: uint32(idleTimeout.Seconds()),
@@ -116,9 +115,9 @@ func tailVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId ne
 
 }
 
-func deleteVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
-	return operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, deleteErr := volumeServerClient.VolumeDelete(ctx, &volume_server_pb.VolumeDeleteRequest{
+func deleteVolume(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
+	return operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, deleteErr := volumeServerClient.VolumeDelete(context.Background(), &volume_server_pb.VolumeDeleteRequest{
 			VolumeId: uint32(volumeId),
 		})
 		return deleteErr
diff --git a/weed/shell/command_volume_tier_download.go b/weed/shell/command_volume_tier_download.go
index 0f1a1bb6e..756dc4686 100644
--- a/weed/shell/command_volume_tier_download.go
+++ b/weed/shell/command_volume_tier_download.go
@@ -49,18 +49,17 @@ func (c *commandVolumeTierDownload) Do(args []string, commandEnv *CommandEnv, wr
 		return nil
 	}
 
-	ctx := context.Background()
 	vid := needle.VolumeId(*volumeId)
 
 	// collect topology information
-	topologyInfo, err := collectTopologyInfo(ctx, commandEnv)
+	topologyInfo, err := collectTopologyInfo(commandEnv)
 	if err != nil {
 		return err
 	}
 
 	// volumeId is provided
 	if vid != 0 {
-		return doVolumeTierDownload(ctx, commandEnv, writer, *collection, vid)
+		return doVolumeTierDownload(commandEnv, writer, *collection, vid)
 	}
 
 	// apply to all volumes in the collection
@@ -71,7 +70,7 @@ func (c *commandVolumeTierDownload) Do(args []string, commandEnv *CommandEnv, wr
 	}
 	fmt.Printf("tier download volumes: %v\n", volumeIds)
 	for _, vid := range volumeIds {
-		if err = doVolumeTierDownload(ctx, commandEnv, writer, *collection, vid); err != nil {
+		if err = doVolumeTierDownload(commandEnv, writer, *collection, vid); err != nil {
 			return err
 		}
 	}
@@ -97,7 +96,7 @@ func collectRemoteVolumes(topoInfo *master_pb.TopologyInfo, selectedCollection s
 	return
 }
 
-func doVolumeTierDownload(ctx context.Context, commandEnv *CommandEnv, writer io.Writer, collection string, vid needle.VolumeId) (err error) {
+func doVolumeTierDownload(commandEnv *CommandEnv, writer io.Writer, collection string, vid needle.VolumeId) (err error) {
 	// find volume location
 	locations, found := commandEnv.MasterClient.GetLocations(uint32(vid))
 	if !found {
@@ -107,7 +106,7 @@ func doVolumeTierDownload(ctx context.Context, commandEnv *CommandEnv, writer io
 	// TODO parallelize this
 	for _, loc := range locations {
 		// copy the .dat file from remote tier to local
-		err = downloadDatFromRemoteTier(ctx, commandEnv.option.GrpcDialOption, writer, needle.VolumeId(vid), collection, loc.Url)
+		err = downloadDatFromRemoteTier(commandEnv.option.GrpcDialOption, writer, needle.VolumeId(vid), collection, loc.Url)
 		if err != nil {
 			return fmt.Errorf("download dat file for volume %d to %s: %v", vid, loc.Url, err)
 		}
@@ -116,10 +115,10 @@ func doVolumeTierDownload(ctx context.Context, commandEnv *CommandEnv, writer io
 	return nil
 }
 
-func downloadDatFromRemoteTier(ctx context.Context, grpcDialOption grpc.DialOption, writer io.Writer, volumeId needle.VolumeId, collection string, targetVolumeServer string) error {
+func downloadDatFromRemoteTier(grpcDialOption grpc.DialOption, writer io.Writer, volumeId needle.VolumeId, collection string, targetVolumeServer string) error {
 
-	err := operation.WithVolumeServerClient(targetVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		stream, downloadErr := volumeServerClient.VolumeTierMoveDatFromRemote(ctx, &volume_server_pb.VolumeTierMoveDatFromRemoteRequest{
+	err := operation.WithVolumeServerClient(targetVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		stream, downloadErr := volumeServerClient.VolumeTierMoveDatFromRemote(context.Background(), &volume_server_pb.VolumeTierMoveDatFromRemoteRequest{
 			VolumeId:   uint32(volumeId),
 			Collection: collection,
 		})
@@ -145,14 +144,14 @@ func downloadDatFromRemoteTier(ctx context.Context, grpcDialOption grpc.DialOpti
 			return downloadErr
 		}
 
-		_, unmountErr := volumeServerClient.VolumeUnmount(ctx, &volume_server_pb.VolumeUnmountRequest{
+		_, unmountErr := volumeServerClient.VolumeUnmount(context.Background(), &volume_server_pb.VolumeUnmountRequest{
 			VolumeId: uint32(volumeId),
 		})
 		if unmountErr != nil {
 			return unmountErr
 		}
 
-		_, mountErr := volumeServerClient.VolumeMount(ctx, &volume_server_pb.VolumeMountRequest{
+		_, mountErr := volumeServerClient.VolumeMount(context.Background(), &volume_server_pb.VolumeMountRequest{
 			VolumeId: uint32(volumeId),
 		})
 		if mountErr != nil {
diff --git a/weed/shell/command_volume_tier_upload.go b/weed/shell/command_volume_tier_upload.go
index 20da1187c..5131e8f85 100644
--- a/weed/shell/command_volume_tier_upload.go
+++ b/weed/shell/command_volume_tier_upload.go
@@ -67,23 +67,22 @@ func (c *commandVolumeTierUpload) Do(args []string, commandEnv *CommandEnv, writ
 		return nil
 	}
 
-	ctx := context.Background()
 	vid := needle.VolumeId(*volumeId)
 
 	// volumeId is provided
 	if vid != 0 {
-		return doVolumeTierUpload(ctx, commandEnv, writer, *collection, vid, *dest, *keepLocalDatFile)
+		return doVolumeTierUpload(commandEnv, writer, *collection, vid, *dest, *keepLocalDatFile)
 	}
 
 	// apply to all volumes in the collection
 	// reusing collectVolumeIdsForEcEncode for now
-	volumeIds, err := collectVolumeIdsForEcEncode(ctx, commandEnv, *collection, *fullPercentage, *quietPeriod)
+	volumeIds, err := collectVolumeIdsForEcEncode(commandEnv, *collection, *fullPercentage, *quietPeriod)
 	if err != nil {
 		return err
 	}
 	fmt.Printf("tier upload volumes: %v\n", volumeIds)
 	for _, vid := range volumeIds {
-		if err = doVolumeTierUpload(ctx, commandEnv, writer, *collection, vid, *dest, *keepLocalDatFile); err != nil {
+		if err = doVolumeTierUpload(commandEnv, writer, *collection, vid, *dest, *keepLocalDatFile); err != nil {
 			return err
 		}
 	}
@@ -91,20 +90,20 @@ func (c *commandVolumeTierUpload) Do(args []string, commandEnv *CommandEnv, writ
 	return nil
 }
 
-func doVolumeTierUpload(ctx context.Context, commandEnv *CommandEnv, writer io.Writer, collection string, vid needle.VolumeId, dest string, keepLocalDatFile bool) (err error) {
+func doVolumeTierUpload(commandEnv *CommandEnv, writer io.Writer, collection string, vid needle.VolumeId, dest string, keepLocalDatFile bool) (err error) {
 	// find volume location
 	locations, found := commandEnv.MasterClient.GetLocations(uint32(vid))
 	if !found {
 		return fmt.Errorf("volume %d not found", vid)
 	}
 
-	err = markVolumeReadonly(ctx, commandEnv.option.GrpcDialOption, needle.VolumeId(vid), locations)
+	err = markVolumeReadonly(commandEnv.option.GrpcDialOption, needle.VolumeId(vid), locations)
 	if err != nil {
 		return fmt.Errorf("mark volume %d as readonly on %s: %v", vid, locations[0].Url, err)
 	}
 
 	// copy the .dat file to remote tier
-	err = uploadDatToRemoteTier(ctx, commandEnv.option.GrpcDialOption, writer, needle.VolumeId(vid), collection, locations[0].Url, dest, keepLocalDatFile)
+	err = uploadDatToRemoteTier(commandEnv.option.GrpcDialOption, writer, needle.VolumeId(vid), collection, locations[0].Url, dest, keepLocalDatFile)
 	if err != nil {
 		return fmt.Errorf("copy dat file for volume %d on %s to %s: %v", vid, locations[0].Url, dest, err)
 	}
@@ -112,10 +111,10 @@ func doVolumeTierUpload(ctx context.Context, commandEnv *CommandEnv, writer io.W
 	return nil
 }
 
-func uploadDatToRemoteTier(ctx context.Context, grpcDialOption grpc.DialOption, writer io.Writer, volumeId needle.VolumeId, collection string, sourceVolumeServer string, dest string, keepLocalDatFile bool) error {
+func uploadDatToRemoteTier(grpcDialOption grpc.DialOption, writer io.Writer, volumeId needle.VolumeId, collection string, sourceVolumeServer string, dest string, keepLocalDatFile bool) error {
 
-	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		stream, copyErr := volumeServerClient.VolumeTierMoveDatToRemote(ctx, &volume_server_pb.VolumeTierMoveDatToRemoteRequest{
+	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		stream, copyErr := volumeServerClient.VolumeTierMoveDatToRemote(context.Background(), &volume_server_pb.VolumeTierMoveDatToRemoteRequest{
 			VolumeId:               uint32(volumeId),
 			Collection:             collection,
 			DestinationBackendName: dest,
diff --git a/weed/shell/command_volume_unmount.go b/weed/shell/command_volume_unmount.go
index 826258dfb..6e5bef485 100644
--- a/weed/shell/command_volume_unmount.go
+++ b/weed/shell/command_volume_unmount.go
@@ -45,14 +45,13 @@ func (c *commandVolumeUnmount) Do(args []string, commandEnv *CommandEnv, writer
 		return fmt.Errorf("wrong volume id format %s: %v", volumeId, err)
 	}
 
-	ctx := context.Background()
-	return unmountVolume(ctx, commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer)
+	return unmountVolume(commandEnv.option.GrpcDialOption, volumeId, sourceVolumeServer)
 
 }
 
-func unmountVolume(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
-	return operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-		_, unmountErr := volumeServerClient.VolumeUnmount(ctx, &volume_server_pb.VolumeUnmountRequest{
+func unmountVolume(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
+	return operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, unmountErr := volumeServerClient.VolumeUnmount(context.Background(), &volume_server_pb.VolumeUnmountRequest{
 			VolumeId: uint32(volumeId),
 		})
 		return unmountErr
diff --git a/weed/shell/commands.go b/weed/shell/commands.go
index f1fcb62d4..31ca31bc3 100644
--- a/weed/shell/commands.go
+++ b/weed/shell/commands.go
@@ -44,7 +44,7 @@ var (
 func NewCommandEnv(options ShellOptions) *CommandEnv {
 	return &CommandEnv{
 		env: make(map[string]string),
-		MasterClient: wdclient.NewMasterClient(context.Background(),
+		MasterClient: wdclient.NewMasterClient(
 			options.GrpcDialOption, "shell", strings.Split(*options.Masters, ",")),
 		option: options,
 	}
@@ -60,19 +60,19 @@ func (ce *CommandEnv) parseUrl(input string) (filerServer string, filerPort int6
 	return ce.option.FilerHost, ce.option.FilerPort, input, err
 }
 
-func (ce *CommandEnv) isDirectory(ctx context.Context, filerServer string, filerPort int64, path string) bool {
+func (ce *CommandEnv) isDirectory(filerServer string, filerPort int64, path string) bool {
 
-	return ce.checkDirectory(ctx, filerServer, filerPort, path) == nil
+	return ce.checkDirectory(filerServer, filerPort, path) == nil
 
 }
 
-func (ce *CommandEnv) checkDirectory(ctx context.Context, filerServer string, filerPort int64, path string) error {
+func (ce *CommandEnv) checkDirectory(filerServer string, filerPort int64, path string) error {
 
 	dir, name := filer2.FullPath(path).DirAndName()
 
-	return ce.withFilerClient(ctx, filerServer, filerPort, func(ctx context.Context, client filer_pb.SeaweedFilerClient) error {
+	return ce.withFilerClient(filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
 
-		resp, lookupErr := client.LookupDirectoryEntry(ctx, &filer_pb.LookupDirectoryEntryRequest{
+		resp, lookupErr := client.LookupDirectoryEntry(context.Background(), &filer_pb.LookupDirectoryEntryRequest{
 			Directory: dir,
 			Name:      name,
 		})
diff --git a/weed/storage/store_ec.go b/weed/storage/store_ec.go
index 47e061d05..e423e7dca 100644
--- a/weed/storage/store_ec.go
+++ b/weed/storage/store_ec.go
@@ -116,7 +116,7 @@ func (s *Store) DestroyEcVolume(vid needle.VolumeId) {
 	}
 }
 
-func (s *Store) ReadEcShardNeedle(ctx context.Context, vid needle.VolumeId, n *needle.Needle) (int, error) {
+func (s *Store) ReadEcShardNeedle(vid needle.VolumeId, n *needle.Needle) (int, error) {
 	for _, location := range s.Locations {
 		if localEcVolume, found := location.FindEcVolume(vid); found {
 
@@ -133,7 +133,7 @@ func (s *Store) ReadEcShardNeedle(ctx context.Context, vid needle.VolumeId, n *n
 			if len(intervals) > 1 {
 				glog.V(3).Infof("ReadEcShardNeedle needle id %s intervals:%+v", n.String(), intervals)
 			}
-			bytes, isDeleted, err := s.readEcShardIntervals(ctx, vid, n.Id, localEcVolume, intervals)
+			bytes, isDeleted, err := s.readEcShardIntervals(vid, n.Id, localEcVolume, intervals)
 			if err != nil {
 				return 0, fmt.Errorf("ReadEcShardIntervals: %v", err)
 			}
@@ -152,14 +152,14 @@ func (s *Store) ReadEcShardNeedle(ctx context.Context, vid needle.VolumeId, n *n
 	return 0, fmt.Errorf("ec shard %d not found", vid)
 }
 
-func (s *Store) readEcShardIntervals(ctx context.Context, vid needle.VolumeId, needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, intervals []erasure_coding.Interval) (data []byte, is_deleted bool, err error) {
+func (s *Store) readEcShardIntervals(vid needle.VolumeId, needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, intervals []erasure_coding.Interval) (data []byte, is_deleted bool, err error) {
 
-	if err = s.cachedLookupEcShardLocations(ctx, ecVolume); err != nil {
+	if err = s.cachedLookupEcShardLocations(ecVolume); err != nil {
 		return nil, false, fmt.Errorf("failed to locate shard via master grpc %s: %v", s.MasterAddress, err)
 	}
 
 	for i, interval := range intervals {
-		if d, isDeleted, e := s.readOneEcShardInterval(ctx, needleId, ecVolume, interval); e != nil {
+		if d, isDeleted, e := s.readOneEcShardInterval(needleId, ecVolume, interval); e != nil {
 			return nil, isDeleted, e
 		} else {
 			if isDeleted {
@@ -175,7 +175,7 @@ func (s *Store) readEcShardIntervals(ctx context.Context, vid needle.VolumeId, n
 	return
 }
 
-func (s *Store) readOneEcShardInterval(ctx context.Context, needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, interval erasure_coding.Interval) (data []byte, is_deleted bool, err error) {
+func (s *Store) readOneEcShardInterval(needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, interval erasure_coding.Interval) (data []byte, is_deleted bool, err error) {
 	shardId, actualOffset := interval.ToShardIdAndOffset(erasure_coding.ErasureCodingLargeBlockSize, erasure_coding.ErasureCodingSmallBlockSize)
 	data = make([]byte, interval.Size)
 	if shard, found := ecVolume.FindEcVolumeShard(shardId); found {
@@ -190,7 +190,7 @@ func (s *Store) readOneEcShardInterval(ctx context.Context, needleId types.Needl
 
 		// try reading directly
 		if hasShardIdLocation {
-			_, is_deleted, err = s.readRemoteEcShardInterval(ctx, sourceDataNodes, needleId, ecVolume.VolumeId, shardId, data, actualOffset)
+			_, is_deleted, err = s.readRemoteEcShardInterval(sourceDataNodes, needleId, ecVolume.VolumeId, shardId, data, actualOffset)
 			if err == nil {
 				return
 			}
@@ -199,7 +199,7 @@ func (s *Store) readOneEcShardInterval(ctx context.Context, needleId types.Needl
 		}
 
 		// try reading by recovering from other shards
-		_, is_deleted, err = s.recoverOneRemoteEcShardInterval(ctx, needleId, ecVolume, shardId, data, actualOffset)
+		_, is_deleted, err = s.recoverOneRemoteEcShardInterval(needleId, ecVolume, shardId, data, actualOffset)
 		if err == nil {
 			return
 		}
@@ -215,7 +215,7 @@ func forgetShardId(ecVolume *erasure_coding.EcVolume, shardId erasure_coding.Sha
 	ecVolume.ShardLocationsLock.Unlock()
 }
 
-func (s *Store) cachedLookupEcShardLocations(ctx context.Context, ecVolume *erasure_coding.EcVolume) (err error) {
+func (s *Store) cachedLookupEcShardLocations(ecVolume *erasure_coding.EcVolume) (err error) {
 
 	shardCount := len(ecVolume.ShardLocations)
 	if shardCount < erasure_coding.DataShardsCount &&
@@ -230,11 +230,11 @@ func (s *Store) cachedLookupEcShardLocations(ctx context.Context, ecVolume *eras
 
 	glog.V(3).Infof("lookup and cache ec volume %d locations", ecVolume.VolumeId)
 
-	err = operation.WithMasterServerClient(s.MasterAddress, s.grpcDialOption, func(ctx context.Context, masterClient master_pb.SeaweedClient) error {
+	err = operation.WithMasterServerClient(s.MasterAddress, s.grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
 		req := &master_pb.LookupEcVolumeRequest{
 			VolumeId: uint32(ecVolume.VolumeId),
 		}
-		resp, err := masterClient.LookupEcVolume(ctx, req)
+		resp, err := masterClient.LookupEcVolume(context.Background(), req)
 		if err != nil {
 			return fmt.Errorf("lookup ec volume %d: %v", ecVolume.VolumeId, err)
 		}
@@ -258,7 +258,7 @@ func (s *Store) cachedLookupEcShardLocations(ctx context.Context, ecVolume *eras
 	return
 }
 
-func (s *Store) readRemoteEcShardInterval(ctx context.Context, sourceDataNodes []string, needleId types.NeedleId, vid needle.VolumeId, shardId erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
+func (s *Store) readRemoteEcShardInterval(sourceDataNodes []string, needleId types.NeedleId, vid needle.VolumeId, shardId erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
 
 	if len(sourceDataNodes) == 0 {
 		return 0, false, fmt.Errorf("failed to find ec shard %d.%d", vid, shardId)
@@ -266,7 +266,7 @@ func (s *Store) readRemoteEcShardInterval(ctx context.Context, sourceDataNodes [
 
 	for _, sourceDataNode := range sourceDataNodes {
 		glog.V(3).Infof("read remote ec shard %d.%d from %s", vid, shardId, sourceDataNode)
-		n, is_deleted, err = s.doReadRemoteEcShardInterval(ctx, sourceDataNode, needleId, vid, shardId, buf, offset)
+		n, is_deleted, err = s.doReadRemoteEcShardInterval(sourceDataNode, needleId, vid, shardId, buf, offset)
 		if err == nil {
 			return
 		}
@@ -276,12 +276,12 @@ func (s *Store) readRemoteEcShardInterval(ctx context.Context, sourceDataNodes [
 	return
 }
 
-func (s *Store) doReadRemoteEcShardInterval(ctx context.Context, sourceDataNode string, needleId types.NeedleId, vid needle.VolumeId, shardId erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
+func (s *Store) doReadRemoteEcShardInterval(sourceDataNode string, needleId types.NeedleId, vid needle.VolumeId, shardId erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
 
-	err = operation.WithVolumeServerClient(sourceDataNode, s.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	err = operation.WithVolumeServerClient(sourceDataNode, s.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
 		// copy data slice
-		shardReadClient, err := client.VolumeEcShardRead(ctx, &volume_server_pb.VolumeEcShardReadRequest{
+		shardReadClient, err := client.VolumeEcShardRead(context.Background(), &volume_server_pb.VolumeEcShardReadRequest{
 			VolumeId: uint32(vid),
 			ShardId:  uint32(shardId),
 			Offset:   offset,
@@ -316,7 +316,7 @@ func (s *Store) doReadRemoteEcShardInterval(ctx context.Context, sourceDataNode
 	return
 }
 
-func (s *Store) recoverOneRemoteEcShardInterval(ctx context.Context, needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, shardIdToRecover erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
+func (s *Store) recoverOneRemoteEcShardInterval(needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, shardIdToRecover erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
 	glog.V(3).Infof("recover ec shard %d.%d from other locations", ecVolume.VolumeId, shardIdToRecover)
 
 	enc, err := reedsolomon.New(erasure_coding.DataShardsCount, erasure_coding.ParityShardsCount)
@@ -344,7 +344,7 @@ func (s *Store) recoverOneRemoteEcShardInterval(ctx context.Context, needleId ty
 		go func(shardId erasure_coding.ShardId, locations []string) {
 			defer wg.Done()
 			data := make([]byte, len(buf))
-			nRead, isDeleted, readErr := s.readRemoteEcShardInterval(ctx, locations, needleId, ecVolume.VolumeId, shardId, data, offset)
+			nRead, isDeleted, readErr := s.readRemoteEcShardInterval(locations, needleId, ecVolume.VolumeId, shardId, data, offset)
 			if readErr != nil {
 				glog.V(3).Infof("recover: readRemoteEcShardInterval %d.%d %d bytes from %+v: %v", ecVolume.VolumeId, shardId, nRead, locations, readErr)
 				forgetShardId(ecVolume, shardId)
diff --git a/weed/storage/store_ec_delete.go b/weed/storage/store_ec_delete.go
index 2ac907f6c..7e2d9e364 100644
--- a/weed/storage/store_ec_delete.go
+++ b/weed/storage/store_ec_delete.go
@@ -14,7 +14,7 @@ import (
 
 func (s *Store) DeleteEcShardNeedle(ctx context.Context, ecVolume *erasure_coding.EcVolume, n *needle.Needle, cookie types.Cookie) (int64, error) {
 
-	count, err := s.ReadEcShardNeedle(ctx, ecVolume.VolumeId, n)
+	count, err := s.ReadEcShardNeedle(ecVolume.VolumeId, n)
 
 	if err != nil {
 		return 0, err
@@ -24,7 +24,7 @@ func (s *Store) DeleteEcShardNeedle(ctx context.Context, ecVolume *erasure_codin
 		return 0, fmt.Errorf("unexpected cookie %x", cookie)
 	}
 
-	if err = s.doDeleteNeedleFromAtLeastOneRemoteEcShards(ctx, ecVolume, n.Id); err != nil {
+	if err = s.doDeleteNeedleFromAtLeastOneRemoteEcShards(ecVolume, n.Id); err != nil {
 		return 0, err
 	}
 
@@ -32,7 +32,7 @@ func (s *Store) DeleteEcShardNeedle(ctx context.Context, ecVolume *erasure_codin
 
 }
 
-func (s *Store) doDeleteNeedleFromAtLeastOneRemoteEcShards(ctx context.Context, ecVolume *erasure_coding.EcVolume, needleId types.NeedleId) error {
+func (s *Store) doDeleteNeedleFromAtLeastOneRemoteEcShards(ecVolume *erasure_coding.EcVolume, needleId types.NeedleId) error {
 
 	_, _, intervals, err := ecVolume.LocateEcShardNeedle(needleId, ecVolume.Version)
 
@@ -43,13 +43,13 @@ func (s *Store) doDeleteNeedleFromAtLeastOneRemoteEcShards(ctx context.Context,
 	shardId, _ := intervals[0].ToShardIdAndOffset(erasure_coding.ErasureCodingLargeBlockSize, erasure_coding.ErasureCodingSmallBlockSize)
 
 	hasDeletionSuccess := false
-	err = s.doDeleteNeedleFromRemoteEcShardServers(ctx, shardId, ecVolume, needleId)
+	err = s.doDeleteNeedleFromRemoteEcShardServers(shardId, ecVolume, needleId)
 	if err == nil {
 		hasDeletionSuccess = true
 	}
 
 	for shardId = erasure_coding.DataShardsCount; shardId < erasure_coding.TotalShardsCount; shardId++ {
-		if parityDeletionError := s.doDeleteNeedleFromRemoteEcShardServers(ctx, shardId, ecVolume, needleId); parityDeletionError == nil {
+		if parityDeletionError := s.doDeleteNeedleFromRemoteEcShardServers(shardId, ecVolume, needleId); parityDeletionError == nil {
 			hasDeletionSuccess = true
 		}
 	}
@@ -62,7 +62,7 @@ func (s *Store) doDeleteNeedleFromAtLeastOneRemoteEcShards(ctx context.Context,
 
 }
 
-func (s *Store) doDeleteNeedleFromRemoteEcShardServers(ctx context.Context, shardId erasure_coding.ShardId, ecVolume *erasure_coding.EcVolume, needleId types.NeedleId) error {
+func (s *Store) doDeleteNeedleFromRemoteEcShardServers(shardId erasure_coding.ShardId, ecVolume *erasure_coding.EcVolume, needleId types.NeedleId) error {
 
 	ecVolume.ShardLocationsLock.RLock()
 	sourceDataNodes, hasShardLocations := ecVolume.ShardLocations[shardId]
@@ -74,7 +74,7 @@ func (s *Store) doDeleteNeedleFromRemoteEcShardServers(ctx context.Context, shar
 
 	for _, sourceDataNode := range sourceDataNodes {
 		glog.V(4).Infof("delete from remote ec shard %d.%d from %s", ecVolume.VolumeId, shardId, sourceDataNode)
-		err := s.doDeleteNeedleFromRemoteEcShard(ctx, sourceDataNode, ecVolume.VolumeId, ecVolume.Collection, ecVolume.Version, needleId)
+		err := s.doDeleteNeedleFromRemoteEcShard(sourceDataNode, ecVolume.VolumeId, ecVolume.Collection, ecVolume.Version, needleId)
 		if err != nil {
 			return err
 		}
@@ -85,12 +85,12 @@ func (s *Store) doDeleteNeedleFromRemoteEcShardServers(ctx context.Context, shar
 
 }
 
-func (s *Store) doDeleteNeedleFromRemoteEcShard(ctx context.Context, sourceDataNode string, vid needle.VolumeId, collection string, version needle.Version, needleId types.NeedleId) error {
+func (s *Store) doDeleteNeedleFromRemoteEcShard(sourceDataNode string, vid needle.VolumeId, collection string, version needle.Version, needleId types.NeedleId) error {
 
-	return operation.WithVolumeServerClient(sourceDataNode, s.grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	return operation.WithVolumeServerClient(sourceDataNode, s.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
 		// copy data slice
-		_, err := client.VolumeEcBlobDelete(ctx, &volume_server_pb.VolumeEcBlobDeleteRequest{
+		_, err := client.VolumeEcBlobDelete(context.Background(), &volume_server_pb.VolumeEcBlobDeleteRequest{
 			VolumeId:   uint32(vid),
 			Collection: collection,
 			FileKey:    uint64(needleId),
diff --git a/weed/storage/volume_backup.go b/weed/storage/volume_backup.go
index 3763d5515..f7075fe2b 100644
--- a/weed/storage/volume_backup.go
+++ b/weed/storage/volume_backup.go
@@ -72,9 +72,9 @@ func (v *Volume) IncrementalBackup(volumeServer string, grpcDialOption grpc.Dial
 
 	writeOffset := int64(startFromOffset)
 
-	err = operation.WithVolumeServerClient(volumeServer, grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	err = operation.WithVolumeServerClient(volumeServer, grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
-		stream, err := client.VolumeIncrementalCopy(ctx, &volume_server_pb.VolumeIncrementalCopyRequest{
+		stream, err := client.VolumeIncrementalCopy(context.Background(), &volume_server_pb.VolumeIncrementalCopyRequest{
 			VolumeId: uint32(v.Id),
 			SinceNs:  appendAtNs,
 		})
diff --git a/weed/topology/allocate_volume.go b/weed/topology/allocate_volume.go
index 6ca987bc5..e5dc48652 100644
--- a/weed/topology/allocate_volume.go
+++ b/weed/topology/allocate_volume.go
@@ -15,7 +15,7 @@ type AllocateVolumeResult struct {
 
 func AllocateVolume(dn *DataNode, grpcDialOption grpc.DialOption, vid needle.VolumeId, option *VolumeGrowOption) error {
 
-	return operation.WithVolumeServerClient(dn.Url(), grpcDialOption, func(ctx context.Context, client volume_server_pb.VolumeServerClient) error {
+	return operation.WithVolumeServerClient(dn.Url(), grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
 
 		_, deleteErr := client.AllocateVolume(context.Background(), &volume_server_pb.AllocateVolumeRequest{
 			VolumeId:           uint32(vid),
diff --git a/weed/topology/topology_vacuum.go b/weed/topology/topology_vacuum.go
index e7dbf9b1e..ca626e973 100644
--- a/weed/topology/topology_vacuum.go
+++ b/weed/topology/topology_vacuum.go
@@ -19,8 +19,8 @@ func batchVacuumVolumeCheck(grpcDialOption grpc.DialOption, vl *VolumeLayout, vi
 	errCount := int32(0)
 	for index, dn := range locationlist.list {
 		go func(index int, url string, vid needle.VolumeId) {
-			err := operation.WithVolumeServerClient(url, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-				resp, err := volumeServerClient.VacuumVolumeCheck(ctx, &volume_server_pb.VacuumVolumeCheckRequest{
+			err := operation.WithVolumeServerClient(url, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+				resp, err := volumeServerClient.VacuumVolumeCheck(context.Background(), &volume_server_pb.VacuumVolumeCheckRequest{
 					VolumeId: uint32(vid),
 				})
 				if err != nil {
@@ -63,8 +63,8 @@ func batchVacuumVolumeCompact(grpcDialOption grpc.DialOption, vl *VolumeLayout,
 	for index, dn := range locationlist.list {
 		go func(index int, url string, vid needle.VolumeId) {
 			glog.V(0).Infoln(index, "Start vacuuming", vid, "on", url)
-			err := operation.WithVolumeServerClient(url, grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-				_, err := volumeServerClient.VacuumVolumeCompact(ctx, &volume_server_pb.VacuumVolumeCompactRequest{
+			err := operation.WithVolumeServerClient(url, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+				_, err := volumeServerClient.VacuumVolumeCompact(context.Background(), &volume_server_pb.VacuumVolumeCompactRequest{
 					VolumeId: uint32(vid),
 				})
 				return err
@@ -93,8 +93,8 @@ func batchVacuumVolumeCommit(grpcDialOption grpc.DialOption, vl *VolumeLayout, v
 	isCommitSuccess := true
 	for _, dn := range locationlist.list {
 		glog.V(0).Infoln("Start Committing vacuum", vid, "on", dn.Url())
-		err := operation.WithVolumeServerClient(dn.Url(), grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-			_, err := volumeServerClient.VacuumVolumeCommit(ctx, &volume_server_pb.VacuumVolumeCommitRequest{
+		err := operation.WithVolumeServerClient(dn.Url(), grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+			_, err := volumeServerClient.VacuumVolumeCommit(context.Background(), &volume_server_pb.VacuumVolumeCommitRequest{
 				VolumeId: uint32(vid),
 			})
 			return err
@@ -114,8 +114,8 @@ func batchVacuumVolumeCommit(grpcDialOption grpc.DialOption, vl *VolumeLayout, v
 func batchVacuumVolumeCleanup(grpcDialOption grpc.DialOption, vl *VolumeLayout, vid needle.VolumeId, locationlist *VolumeLocationList) {
 	for _, dn := range locationlist.list {
 		glog.V(0).Infoln("Start cleaning up", vid, "on", dn.Url())
-		err := operation.WithVolumeServerClient(dn.Url(), grpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error {
-			_, err := volumeServerClient.VacuumVolumeCleanup(ctx, &volume_server_pb.VacuumVolumeCleanupRequest{
+		err := operation.WithVolumeServerClient(dn.Url(), grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+			_, err := volumeServerClient.VacuumVolumeCleanup(context.Background(), &volume_server_pb.VacuumVolumeCleanupRequest{
 				VolumeId: uint32(vid),
 			})
 			return err
diff --git a/weed/util/grpc_client_server.go b/weed/util/grpc_client_server.go
index 7e396342b..4dace5e8b 100644
--- a/weed/util/grpc_client_server.go
+++ b/weed/util/grpc_client_server.go
@@ -57,14 +57,14 @@ func GrpcDial(ctx context.Context, address string, opts ...grpc.DialOption) (*gr
 	return grpc.DialContext(ctx, address, options...)
 }
 
-func WithCachedGrpcClient(ctx context.Context, fn func(context.Context, *grpc.ClientConn) error, address string, opts ...grpc.DialOption) error {
+func WithCachedGrpcClient(fn func(*grpc.ClientConn) error, address string, opts ...grpc.DialOption) error {
 
 	grpcClientsLock.Lock()
 
 	existingConnection, found := grpcClients[address]
 	if found {
 		grpcClientsLock.Unlock()
-		err := fn(ctx, existingConnection)
+		err := fn(existingConnection)
 		if err != nil {
 			grpcClientsLock.Lock()
 			delete(grpcClients, address)
@@ -74,7 +74,7 @@ func WithCachedGrpcClient(ctx context.Context, fn func(context.Context, *grpc.Cl
 		return err
 	}
 
-	grpcConnection, err := GrpcDial(ctx, address, opts...)
+	grpcConnection, err := GrpcDial(context.Background(), address, opts...)
 	if err != nil {
 		grpcClientsLock.Unlock()
 		return fmt.Errorf("fail to dial %s: %v", address, err)
@@ -83,7 +83,7 @@ func WithCachedGrpcClient(ctx context.Context, fn func(context.Context, *grpc.Cl
 	grpcClients[address] = grpcConnection
 	grpcClientsLock.Unlock()
 
-	err = fn(ctx, grpcConnection)
+	err = fn(grpcConnection)
 	if err != nil {
 		grpcClientsLock.Lock()
 		delete(grpcClients, address)
diff --git a/weed/wdclient/masterclient.go b/weed/wdclient/masterclient.go
index 30b0cf160..f197fa6f2 100644
--- a/weed/wdclient/masterclient.go
+++ b/weed/wdclient/masterclient.go
@@ -13,7 +13,6 @@ import (
 )
 
 type MasterClient struct {
-	ctx            context.Context
 	name           string
 	currentMaster  string
 	masters        []string
@@ -22,9 +21,8 @@ type MasterClient struct {
 	vidMap
 }
 
-func NewMasterClient(ctx context.Context, grpcDialOption grpc.DialOption, clientName string, masters []string) *MasterClient {
+func NewMasterClient(grpcDialOption grpc.DialOption, clientName string, masters []string) *MasterClient {
 	return &MasterClient{
-		ctx:            ctx,
 		name:           clientName,
 		masters:        masters,
 		grpcDialOption: grpcDialOption,
@@ -66,9 +64,9 @@ func (mc *MasterClient) tryAllMasters() {
 
 func (mc *MasterClient) tryConnectToMaster(master string) (nextHintedLeader string) {
 	glog.V(1).Infof("%s Connecting to master %v", mc.name, master)
-	gprcErr := withMasterClient(context.Background(), master, mc.grpcDialOption, func(ctx context.Context, client master_pb.SeaweedClient) error {
+	gprcErr := withMasterClient(master, mc.grpcDialOption, func(client master_pb.SeaweedClient) error {
 
-		stream, err := client.KeepConnected(ctx)
+		stream, err := client.KeepConnected(context.Background())
 		if err != nil {
 			glog.V(0).Infof("%s failed to keep connected to %s: %v", mc.name, master, err)
 			return err
@@ -118,22 +116,22 @@ func (mc *MasterClient) tryConnectToMaster(master string) (nextHintedLeader stri
 	return
 }
 
-func withMasterClient(ctx context.Context, master string, grpcDialOption grpc.DialOption, fn func(ctx context.Context, client master_pb.SeaweedClient) error) error {
+func withMasterClient(master string, grpcDialOption grpc.DialOption, fn func(client master_pb.SeaweedClient) error) error {
 
 	masterGrpcAddress, parseErr := util.ParseServerToGrpcAddress(master)
 	if parseErr != nil {
 		return fmt.Errorf("failed to parse master grpc %v: %v", master, parseErr)
 	}
 
-	return util.WithCachedGrpcClient(ctx, func(ctx2 context.Context, grpcConnection *grpc.ClientConn) error {
+	return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
 		client := master_pb.NewSeaweedClient(grpcConnection)
-		return fn(ctx2, client)
+		return fn(client)
 	}, masterGrpcAddress, grpcDialOption)
 
 }
 
-func (mc *MasterClient) WithClient(ctx context.Context, fn func(client master_pb.SeaweedClient) error) error {
-	return withMasterClient(ctx, mc.currentMaster, mc.grpcDialOption, func(ctx context.Context, client master_pb.SeaweedClient) error {
+func (mc *MasterClient) WithClient(fn func(client master_pb.SeaweedClient) error) error {
+	return withMasterClient(mc.currentMaster, mc.grpcDialOption, func(client master_pb.SeaweedClient) error {
 		return fn(client)
 	})
 }