seaweedfs/weed/shell/command_ec_common.go
2024-11-21 08:54:03 -08:00

862 lines
28 KiB
Go

package shell
import (
"context"
"fmt"
"math/rand/v2"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/operation"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
"github.com/seaweedfs/seaweedfs/weed/pb/volume_server_pb"
"github.com/seaweedfs/seaweedfs/weed/storage/erasure_coding"
"github.com/seaweedfs/seaweedfs/weed/storage/needle"
"github.com/seaweedfs/seaweedfs/weed/storage/super_block"
"github.com/seaweedfs/seaweedfs/weed/storage/types"
"golang.org/x/exp/slices"
"google.golang.org/grpc"
)
type DataCenterId string
type EcNodeId string
type RackId string
type EcNode struct {
info *master_pb.DataNodeInfo
dc DataCenterId
rack RackId
freeEcSlot int
}
type CandidateEcNode struct {
ecNode *EcNode
shardCount int
}
type EcRack struct {
ecNodes map[EcNodeId]*EcNode
freeEcSlot int
}
func moveMountedShardToEcNode(commandEnv *CommandEnv, existingLocation *EcNode, collection string, vid needle.VolumeId, shardId erasure_coding.ShardId, destinationEcNode *EcNode, applyBalancing bool) (err error) {
if !commandEnv.isLocked() {
return fmt.Errorf("lock is lost")
}
copiedShardIds := []uint32{uint32(shardId)}
if applyBalancing {
existingServerAddress := pb.NewServerAddressFromDataNode(existingLocation.info)
// ask destination node to copy shard and the ecx file from source node, and mount it
copiedShardIds, err = oneServerCopyAndMountEcShardsFromSource(commandEnv.option.GrpcDialOption, destinationEcNode, []uint32{uint32(shardId)}, vid, collection, existingServerAddress)
if err != nil {
return err
}
// unmount the to be deleted shards
err = unmountEcShards(commandEnv.option.GrpcDialOption, vid, existingServerAddress, copiedShardIds)
if err != nil {
return err
}
// ask source node to delete the shard, and maybe the ecx file
err = sourceServerDeleteEcShards(commandEnv.option.GrpcDialOption, collection, vid, existingServerAddress, copiedShardIds)
if err != nil {
return err
}
fmt.Printf("moved ec shard %d.%d %s => %s\n", vid, shardId, existingLocation.info.Id, destinationEcNode.info.Id)
}
destinationEcNode.addEcVolumeShards(vid, collection, copiedShardIds)
existingLocation.deleteEcVolumeShards(vid, copiedShardIds)
return nil
}
func oneServerCopyAndMountEcShardsFromSource(grpcDialOption grpc.DialOption,
targetServer *EcNode, shardIdsToCopy []uint32,
volumeId needle.VolumeId, collection string, existingLocation pb.ServerAddress) (copiedShardIds []uint32, err error) {
fmt.Printf("allocate %d.%v %s => %s\n", volumeId, shardIdsToCopy, existingLocation, targetServer.info.Id)
targetAddress := pb.NewServerAddressFromDataNode(targetServer.info)
err = operation.WithVolumeServerClient(false, targetAddress, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
if targetAddress != existingLocation {
fmt.Printf("copy %d.%v %s => %s\n", volumeId, shardIdsToCopy, existingLocation, targetServer.info.Id)
_, copyErr := volumeServerClient.VolumeEcShardsCopy(context.Background(), &volume_server_pb.VolumeEcShardsCopyRequest{
VolumeId: uint32(volumeId),
Collection: collection,
ShardIds: shardIdsToCopy,
CopyEcxFile: true,
CopyEcjFile: true,
CopyVifFile: true,
SourceDataNode: string(existingLocation),
})
if copyErr != nil {
return fmt.Errorf("copy %d.%v %s => %s : %v\n", volumeId, shardIdsToCopy, existingLocation, targetServer.info.Id, copyErr)
}
}
fmt.Printf("mount %d.%v on %s\n", volumeId, shardIdsToCopy, targetServer.info.Id)
_, mountErr := volumeServerClient.VolumeEcShardsMount(context.Background(), &volume_server_pb.VolumeEcShardsMountRequest{
VolumeId: uint32(volumeId),
Collection: collection,
ShardIds: shardIdsToCopy,
})
if mountErr != nil {
return fmt.Errorf("mount %d.%v on %s : %v\n", volumeId, shardIdsToCopy, targetServer.info.Id, mountErr)
}
if targetAddress != existingLocation {
copiedShardIds = shardIdsToCopy
glog.V(0).Infof("%s ec volume %d deletes shards %+v", existingLocation, volumeId, copiedShardIds)
}
return nil
})
if err != nil {
return
}
return
}
func eachDataNode(topo *master_pb.TopologyInfo, fn func(dc DataCenterId, rack RackId, dn *master_pb.DataNodeInfo)) {
for _, dc := range topo.DataCenterInfos {
for _, rack := range dc.RackInfos {
for _, dn := range rack.DataNodeInfos {
fn(DataCenterId(dc.Id), RackId(rack.Id), dn)
}
}
}
}
func sortEcNodesByFreeslotsDescending(ecNodes []*EcNode) {
slices.SortFunc(ecNodes, func(a, b *EcNode) int {
return b.freeEcSlot - a.freeEcSlot
})
}
func sortEcNodesByFreeslotsAscending(ecNodes []*EcNode) {
slices.SortFunc(ecNodes, func(a, b *EcNode) int {
return a.freeEcSlot - b.freeEcSlot
})
}
// if the index node changed the freeEcSlot, need to keep every EcNode still sorted
func ensureSortedEcNodes(data []*CandidateEcNode, index int, lessThan func(i, j int) bool) {
for i := index - 1; i >= 0; i-- {
if lessThan(i+1, i) {
swap(data, i, i+1)
} else {
break
}
}
for i := index + 1; i < len(data); i++ {
if lessThan(i, i-1) {
swap(data, i, i-1)
} else {
break
}
}
}
func swap(data []*CandidateEcNode, i, j int) {
t := data[i]
data[i] = data[j]
data[j] = t
}
func countShards(ecShardInfos []*master_pb.VolumeEcShardInformationMessage) (count int) {
for _, ecShardInfo := range ecShardInfos {
shardBits := erasure_coding.ShardBits(ecShardInfo.EcIndexBits)
count += shardBits.ShardIdCount()
}
return
}
func countFreeShardSlots(dn *master_pb.DataNodeInfo, diskType types.DiskType) (count int) {
if dn.DiskInfos == nil {
return 0
}
diskInfo := dn.DiskInfos[string(diskType)]
if diskInfo == nil {
return 0
}
return int(diskInfo.MaxVolumeCount-diskInfo.VolumeCount)*erasure_coding.DataShardsCount - countShards(diskInfo.EcShardInfos)
}
func (ecNode *EcNode) localShardIdCount(vid uint32) int {
for _, diskInfo := range ecNode.info.DiskInfos {
for _, ecShardInfo := range diskInfo.EcShardInfos {
if vid == ecShardInfo.Id {
shardBits := erasure_coding.ShardBits(ecShardInfo.EcIndexBits)
return shardBits.ShardIdCount()
}
}
}
return 0
}
func collectEcNodes(commandEnv *CommandEnv, selectedDataCenter string) (ecNodes []*EcNode, totalFreeEcSlots int, err error) {
// list all possible locations
// collect topology information
topologyInfo, _, err := collectTopologyInfo(commandEnv, 0)
if err != nil {
return
}
// find out all volume servers with one slot left.
ecNodes, totalFreeEcSlots = collectEcVolumeServersByDc(topologyInfo, selectedDataCenter)
sortEcNodesByFreeslotsDescending(ecNodes)
return
}
func collectEcVolumeServersByDc(topo *master_pb.TopologyInfo, selectedDataCenter string) (ecNodes []*EcNode, totalFreeEcSlots int) {
eachDataNode(topo, func(dc DataCenterId, rack RackId, dn *master_pb.DataNodeInfo) {
if selectedDataCenter != "" && selectedDataCenter != string(dc) {
return
}
freeEcSlots := countFreeShardSlots(dn, types.HardDriveType)
ecNodes = append(ecNodes, &EcNode{
info: dn,
dc: dc,
rack: rack,
freeEcSlot: int(freeEcSlots),
})
totalFreeEcSlots += freeEcSlots
})
return
}
func sourceServerDeleteEcShards(grpcDialOption grpc.DialOption, collection string, volumeId needle.VolumeId, sourceLocation pb.ServerAddress, toBeDeletedShardIds []uint32) error {
fmt.Printf("delete %d.%v from %s\n", volumeId, toBeDeletedShardIds, sourceLocation)
return operation.WithVolumeServerClient(false, 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,
})
return deleteErr
})
}
func unmountEcShards(grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceLocation pb.ServerAddress, toBeUnmountedhardIds []uint32) error {
fmt.Printf("unmount %d.%v from %s\n", volumeId, toBeUnmountedhardIds, sourceLocation)
return operation.WithVolumeServerClient(false, sourceLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
_, deleteErr := volumeServerClient.VolumeEcShardsUnmount(context.Background(), &volume_server_pb.VolumeEcShardsUnmountRequest{
VolumeId: uint32(volumeId),
ShardIds: toBeUnmountedhardIds,
})
return deleteErr
})
}
func mountEcShards(grpcDialOption grpc.DialOption, collection string, volumeId needle.VolumeId, sourceLocation pb.ServerAddress, toBeMountedhardIds []uint32) error {
fmt.Printf("mount %d.%v on %s\n", volumeId, toBeMountedhardIds, sourceLocation)
return operation.WithVolumeServerClient(false, 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,
})
return mountErr
})
}
func ceilDivide(a, b int) int {
var r int
if (a % b) != 0 {
r = 1
}
return (a / b) + r
}
func findEcVolumeShards(ecNode *EcNode, vid needle.VolumeId) erasure_coding.ShardBits {
if diskInfo, found := ecNode.info.DiskInfos[string(types.HardDriveType)]; found {
for _, shardInfo := range diskInfo.EcShardInfos {
if needle.VolumeId(shardInfo.Id) == vid {
return erasure_coding.ShardBits(shardInfo.EcIndexBits)
}
}
}
return 0
}
func (ecNode *EcNode) addEcVolumeShards(vid needle.VolumeId, collection string, shardIds []uint32) *EcNode {
foundVolume := false
diskInfo, found := ecNode.info.DiskInfos[string(types.HardDriveType)]
if found {
for _, shardInfo := range diskInfo.EcShardInfos {
if needle.VolumeId(shardInfo.Id) == vid {
oldShardBits := erasure_coding.ShardBits(shardInfo.EcIndexBits)
newShardBits := oldShardBits
for _, shardId := range shardIds {
newShardBits = newShardBits.AddShardId(erasure_coding.ShardId(shardId))
}
shardInfo.EcIndexBits = uint32(newShardBits)
ecNode.freeEcSlot -= newShardBits.ShardIdCount() - oldShardBits.ShardIdCount()
foundVolume = true
break
}
}
} else {
diskInfo = &master_pb.DiskInfo{
Type: string(types.HardDriveType),
}
ecNode.info.DiskInfos[string(types.HardDriveType)] = diskInfo
}
if !foundVolume {
var newShardBits erasure_coding.ShardBits
for _, shardId := range shardIds {
newShardBits = newShardBits.AddShardId(erasure_coding.ShardId(shardId))
}
diskInfo.EcShardInfos = append(diskInfo.EcShardInfos, &master_pb.VolumeEcShardInformationMessage{
Id: uint32(vid),
Collection: collection,
EcIndexBits: uint32(newShardBits),
DiskType: string(types.HardDriveType),
})
ecNode.freeEcSlot -= len(shardIds)
}
return ecNode
}
func (ecNode *EcNode) deleteEcVolumeShards(vid needle.VolumeId, shardIds []uint32) *EcNode {
if diskInfo, found := ecNode.info.DiskInfos[string(types.HardDriveType)]; found {
for _, shardInfo := range diskInfo.EcShardInfos {
if needle.VolumeId(shardInfo.Id) == vid {
oldShardBits := erasure_coding.ShardBits(shardInfo.EcIndexBits)
newShardBits := oldShardBits
for _, shardId := range shardIds {
newShardBits = newShardBits.RemoveShardId(erasure_coding.ShardId(shardId))
}
shardInfo.EcIndexBits = uint32(newShardBits)
ecNode.freeEcSlot -= newShardBits.ShardIdCount() - oldShardBits.ShardIdCount()
}
}
}
return ecNode
}
func groupByCount(data []*EcNode, identifierFn func(*EcNode) (id string, count int)) map[string]int {
countMap := make(map[string]int)
for _, d := range data {
id, count := identifierFn(d)
countMap[id] += count
}
return countMap
}
func groupBy(data []*EcNode, identifierFn func(*EcNode) (id string)) map[string][]*EcNode {
groupMap := make(map[string][]*EcNode)
for _, d := range data {
id := identifierFn(d)
groupMap[id] = append(groupMap[id], d)
}
return groupMap
}
func collectRacks(allEcNodes []*EcNode) map[RackId]*EcRack {
// collect racks info
racks := make(map[RackId]*EcRack)
for _, ecNode := range allEcNodes {
if racks[ecNode.rack] == nil {
racks[ecNode.rack] = &EcRack{
ecNodes: make(map[EcNodeId]*EcNode),
}
}
racks[ecNode.rack].ecNodes[EcNodeId(ecNode.info.Id)] = ecNode
racks[ecNode.rack].freeEcSlot += ecNode.freeEcSlot
}
return racks
}
func balanceEcVolumes(commandEnv *CommandEnv, collection string, allEcNodes []*EcNode, racks map[RackId]*EcRack, applyBalancing bool) error {
fmt.Printf("balanceEcVolumes %s\n", collection)
if err := deleteDuplicatedEcShards(commandEnv, allEcNodes, collection, applyBalancing); err != nil {
return fmt.Errorf("delete duplicated collection %s ec shards: %v", collection, err)
}
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(commandEnv, allEcNodes, racks, collection, applyBalancing); err != nil {
return fmt.Errorf("balance within racks collection %s ec shards: %v", collection, err)
}
return nil
}
func deleteDuplicatedEcShards(commandEnv *CommandEnv, allEcNodes []*EcNode, collection string, applyBalancing bool) error {
// vid => []ecNode
vidLocations := collectVolumeIdToEcNodes(allEcNodes, collection)
// deduplicate ec shards
for vid, locations := range vidLocations {
if err := doDeduplicateEcShards(commandEnv, collection, vid, locations, applyBalancing); err != nil {
return err
}
}
return nil
}
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)
for _, ecNode := range locations {
shardBits := findEcVolumeShards(ecNode, vid)
for _, shardId := range shardBits.ShardIds() {
shardToLocations[shardId] = append(shardToLocations[shardId], ecNode)
}
}
for shardId, ecNodes := range shardToLocations {
if len(ecNodes) <= 1 {
continue
}
sortEcNodesByFreeslotsAscending(ecNodes)
fmt.Printf("ec shard %d.%d has %d copies, keeping %v\n", vid, shardId, len(ecNodes), ecNodes[0].info.Id)
if !applyBalancing {
continue
}
duplicatedShardIds := []uint32{uint32(shardId)}
for _, ecNode := range ecNodes[1:] {
if err := unmountEcShards(commandEnv.option.GrpcDialOption, vid, pb.NewServerAddressFromDataNode(ecNode.info), duplicatedShardIds); err != nil {
return err
}
if err := sourceServerDeleteEcShards(commandEnv.option.GrpcDialOption, collection, vid, pb.NewServerAddressFromDataNode(ecNode.info), duplicatedShardIds); err != nil {
return err
}
ecNode.deleteEcVolumeShards(vid, duplicatedShardIds)
}
}
return nil
}
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, collection)
// spread the ec shards evenly
for vid, locations := range vidLocations {
if err := doBalanceEcShardsAcrossRacks(commandEnv, collection, vid, locations, racks, applyBalancing); err != nil {
return err
}
}
return nil
}
func countShardsByRack(vid needle.VolumeId, locations []*EcNode) map[string]int {
return groupByCount(locations, func(ecNode *EcNode) (id string, count int) {
shardBits := findEcVolumeShards(ecNode, vid)
return string(ecNode.rack), shardBits.ShardIdCount()
})
}
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))
// see the volume's shards are in how many racks, and how many in each rack
rackToShardCount := countShardsByRack(vid, locations)
rackEcNodesWithVid := groupBy(locations, func(ecNode *EcNode) string {
return string(ecNode.rack)
})
// ecShardsToMove = select overflown ec shards from racks with ec shard counts > averageShardsPerEcRack
ecShardsToMove := make(map[erasure_coding.ShardId]*EcNode)
for rackId, count := range rackToShardCount {
if count <= averageShardsPerEcRack {
continue
}
possibleEcNodes := rackEcNodesWithVid[rackId]
for shardId, ecNode := range pickNEcShardsToMoveFrom(possibleEcNodes, vid, count-averageShardsPerEcRack) {
ecShardsToMove[shardId] = ecNode
}
}
for shardId, ecNode := range ecShardsToMove {
// TODO: consider volume replica info when balancing racks
rackId := pickRackToBalanceShardsInto(racks, rackToShardCount, nil, averageShardsPerEcRack)
if rackId == "" {
fmt.Printf("ec shard %d.%d at %s can not find a destination rack\n", vid, shardId, ecNode.info.Id)
continue
}
var possibleDestinationEcNodes []*EcNode
for _, n := range racks[rackId].ecNodes {
possibleDestinationEcNodes = append(possibleDestinationEcNodes, n)
}
err := pickOneEcNodeAndMoveOneShard(commandEnv, averageShardsPerEcRack, ecNode, collection, vid, shardId, possibleDestinationEcNodes, applyBalancing)
if err != nil {
return err
}
rackToShardCount[string(rackId)] += 1
rackToShardCount[string(ecNode.rack)] -= 1
racks[rackId].freeEcSlot -= 1
racks[ecNode.rack].freeEcSlot += 1
}
return nil
}
func pickRackToBalanceShardsInto(rackToEcNodes map[RackId]*EcRack, rackToShardCount map[string]int, replicaPlacement *super_block.ReplicaPlacement, averageShardsPerEcRack int) RackId {
targets := []RackId{}
targetShards := -1
for _, shards := range rackToShardCount {
if shards > targetShards {
targetShards = shards
}
}
for rackId, rack := range rackToEcNodes {
shards := rackToShardCount[string(rackId)]
if rack.freeEcSlot <= 0 {
// No EC shards slots left :(
continue
}
if replicaPlacement != nil && shards >= replicaPlacement.DiffRackCount {
// Don't select racks with more EC shards for the target volume than the replicaton limit.
continue
}
if shards >= averageShardsPerEcRack {
// Keep EC shards across racks as balanced as possible.
continue
}
if shards < targetShards {
// Favor racks with less shards, to ensure an uniform distribution.
targets = nil
targetShards = shards
}
if shards == targetShards {
targets = append(targets, rackId)
}
}
if len(targets) == 0 {
return ""
}
return targets[rand.IntN(len(targets))]
}
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, collection)
// spread the ec shards evenly
for vid, locations := range vidLocations {
// see the volume's shards are in how many racks, and how many in each rack
rackToShardCount := groupByCount(locations, func(ecNode *EcNode) (id string, count int) {
shardBits := findEcVolumeShards(ecNode, vid)
return string(ecNode.rack), shardBits.ShardIdCount()
})
rackEcNodesWithVid := groupBy(locations, func(ecNode *EcNode) string {
return string(ecNode.rack)
})
for rackId, _ := range rackToShardCount {
var possibleDestinationEcNodes []*EcNode
for _, n := range racks[RackId(rackId)].ecNodes {
if _, found := n.info.DiskInfos[string(types.HardDriveType)]; found {
possibleDestinationEcNodes = append(possibleDestinationEcNodes, n)
}
}
sourceEcNodes := rackEcNodesWithVid[rackId]
averageShardsPerEcNode := ceilDivide(rackToShardCount[rackId], len(possibleDestinationEcNodes))
if err := doBalanceEcShardsWithinOneRack(commandEnv, averageShardsPerEcNode, collection, vid, sourceEcNodes, possibleDestinationEcNodes, applyBalancing); err != nil {
return err
}
}
}
return nil
}
func doBalanceEcShardsWithinOneRack(commandEnv *CommandEnv, averageShardsPerEcNode int, collection string, vid needle.VolumeId, existingLocations, possibleDestinationEcNodes []*EcNode, applyBalancing bool) error {
for _, ecNode := range existingLocations {
shardBits := findEcVolumeShards(ecNode, vid)
overLimitCount := shardBits.ShardIdCount() - averageShardsPerEcNode
for _, shardId := range shardBits.ShardIds() {
if overLimitCount <= 0 {
break
}
fmt.Printf("%s has %d overlimit, moving ec shard %d.%d\n", ecNode.info.Id, overLimitCount, vid, shardId)
err := pickOneEcNodeAndMoveOneShard(commandEnv, averageShardsPerEcNode, ecNode, collection, vid, shardId, possibleDestinationEcNodes, applyBalancing)
if err != nil {
return err
}
overLimitCount--
}
}
return nil
}
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(commandEnv, ecRack, applyBalancing); err != nil {
return err
}
}
return nil
}
func doBalanceEcRack(commandEnv *CommandEnv, ecRack *EcRack, applyBalancing bool) error {
if len(ecRack.ecNodes) <= 1 {
return nil
}
var rackEcNodes []*EcNode
for _, node := range ecRack.ecNodes {
rackEcNodes = append(rackEcNodes, node)
}
ecNodeIdToShardCount := groupByCount(rackEcNodes, func(ecNode *EcNode) (id string, count int) {
diskInfo, found := ecNode.info.DiskInfos[string(types.HardDriveType)]
if !found {
return
}
for _, ecShardInfo := range diskInfo.EcShardInfos {
count += erasure_coding.ShardBits(ecShardInfo.EcIndexBits).ShardIdCount()
}
return ecNode.info.Id, count
})
var totalShardCount int
for _, count := range ecNodeIdToShardCount {
totalShardCount += count
}
averageShardCount := ceilDivide(totalShardCount, len(rackEcNodes))
hasMove := true
for hasMove {
hasMove = false
slices.SortFunc(rackEcNodes, func(a, b *EcNode) int {
return b.freeEcSlot - a.freeEcSlot
})
emptyNode, fullNode := rackEcNodes[0], rackEcNodes[len(rackEcNodes)-1]
emptyNodeShardCount, fullNodeShardCount := ecNodeIdToShardCount[emptyNode.info.Id], ecNodeIdToShardCount[fullNode.info.Id]
if fullNodeShardCount > averageShardCount && emptyNodeShardCount+1 <= averageShardCount {
emptyNodeIds := make(map[uint32]bool)
if emptyDiskInfo, found := emptyNode.info.DiskInfos[string(types.HardDriveType)]; found {
for _, shards := range emptyDiskInfo.EcShardInfos {
emptyNodeIds[shards.Id] = true
}
}
if fullDiskInfo, found := fullNode.info.DiskInfos[string(types.HardDriveType)]; found {
for _, shards := range fullDiskInfo.EcShardInfos {
if _, found := emptyNodeIds[shards.Id]; !found {
for _, shardId := range erasure_coding.ShardBits(shards.EcIndexBits).ShardIds() {
fmt.Printf("%s moves ec shards %d.%d to %s\n", fullNode.info.Id, shards.Id, shardId, emptyNode.info.Id)
err := moveMountedShardToEcNode(commandEnv, fullNode, shards.Collection, needle.VolumeId(shards.Id), shardId, emptyNode, applyBalancing)
if err != nil {
return err
}
ecNodeIdToShardCount[emptyNode.info.Id]++
ecNodeIdToShardCount[fullNode.info.Id]--
hasMove = true
break
}
break
}
}
}
}
}
return nil
}
func pickOneEcNodeAndMoveOneShard(commandEnv *CommandEnv, averageShardsPerEcNode int, existingLocation *EcNode, collection string, vid needle.VolumeId, shardId erasure_coding.ShardId, possibleDestinationEcNodes []*EcNode, applyBalancing bool) error {
sortEcNodesByFreeslotsDescending(possibleDestinationEcNodes)
skipReason := ""
for _, destEcNode := range possibleDestinationEcNodes {
if destEcNode.info.Id == existingLocation.info.Id {
continue
}
if destEcNode.freeEcSlot <= 0 {
skipReason += fmt.Sprintf(" Skipping %s because it has no free slots\n", destEcNode.info.Id)
continue
}
if findEcVolumeShards(destEcNode, vid).ShardIdCount() >= averageShardsPerEcNode {
skipReason += fmt.Sprintf(" Skipping %s because it %d >= avernageShards (%d)\n",
destEcNode.info.Id, findEcVolumeShards(destEcNode, vid).ShardIdCount(), averageShardsPerEcNode)
continue
}
fmt.Printf("%s moves ec shard %d.%d to %s\n", existingLocation.info.Id, vid, shardId, destEcNode.info.Id)
err := moveMountedShardToEcNode(commandEnv, existingLocation, collection, vid, shardId, destEcNode, applyBalancing)
if err != nil {
return err
}
return nil
}
fmt.Printf("WARNING: Could not find suitable taget node for %d.%d:\n%s", vid, shardId, skipReason)
return nil
}
func pickNEcShardsToMoveFrom(ecNodes []*EcNode, vid needle.VolumeId, n int) map[erasure_coding.ShardId]*EcNode {
picked := make(map[erasure_coding.ShardId]*EcNode)
var candidateEcNodes []*CandidateEcNode
for _, ecNode := range ecNodes {
shardBits := findEcVolumeShards(ecNode, vid)
if shardBits.ShardIdCount() > 0 {
candidateEcNodes = append(candidateEcNodes, &CandidateEcNode{
ecNode: ecNode,
shardCount: shardBits.ShardIdCount(),
})
}
}
slices.SortFunc(candidateEcNodes, func(a, b *CandidateEcNode) int {
return b.shardCount - a.shardCount
})
for i := 0; i < n; i++ {
selectedEcNodeIndex := -1
for i, candidateEcNode := range candidateEcNodes {
shardBits := findEcVolumeShards(candidateEcNode.ecNode, vid)
if shardBits > 0 {
selectedEcNodeIndex = i
for _, shardId := range shardBits.ShardIds() {
candidateEcNode.shardCount--
picked[shardId] = candidateEcNode.ecNode
candidateEcNode.ecNode.deleteEcVolumeShards(vid, []uint32{uint32(shardId)})
break
}
break
}
}
if selectedEcNodeIndex >= 0 {
ensureSortedEcNodes(candidateEcNodes, selectedEcNodeIndex, func(i, j int) bool {
return candidateEcNodes[i].shardCount > candidateEcNodes[j].shardCount
})
}
}
return picked
}
func collectVolumeIdToEcNodes(allEcNodes []*EcNode, collection string) map[needle.VolumeId][]*EcNode {
vidLocations := make(map[needle.VolumeId][]*EcNode)
for _, ecNode := range allEcNodes {
diskInfo, found := ecNode.info.DiskInfos[string(types.HardDriveType)]
if !found {
continue
}
for _, shardInfo := range diskInfo.EcShardInfos {
// ignore if not in current collection
if shardInfo.Collection == collection {
vidLocations[needle.VolumeId(shardInfo.Id)] = append(vidLocations[needle.VolumeId(shardInfo.Id)], ecNode)
}
}
}
return vidLocations
}
// TODO: EC volumes have no replica placement info :( Maybe rely on the master's default?
func volumeIdToReplicaPlacement(vid needle.VolumeId, nodes []*EcNode) (*super_block.ReplicaPlacement, error) {
for _, ecNode := range nodes {
for _, diskInfo := range ecNode.info.DiskInfos {
for _, volumeInfo := range diskInfo.VolumeInfos {
if needle.VolumeId(volumeInfo.Id) != vid {
continue
}
return super_block.NewReplicaPlacementFromByte(byte(volumeInfo.ReplicaPlacement))
}
}
}
return nil, fmt.Errorf("failed to resolve replica placement for volume ID %d", vid)
}
func getDefaultReplicaPlacement(commandEnv *CommandEnv) (*super_block.ReplicaPlacement, error) {
var resp *master_pb.GetMasterConfigurationResponse
var err error
err = commandEnv.MasterClient.WithClient(false, func(client master_pb.SeaweedClient) error {
resp, err = client.GetMasterConfiguration(context.Background(), &master_pb.GetMasterConfigurationRequest{})
return err
})
if err != nil {
return nil, err
}
return super_block.NewReplicaPlacementFromString(resp.DefaultReplication)
}
func EcBalance(commandEnv *CommandEnv, collections []string, dc string, applyBalancing bool) (err error) {
if len(collections) == 0 {
return fmt.Errorf("no collections to balance")
}
// collect all ec nodes
allEcNodes, totalFreeEcSlots, err := collectEcNodes(commandEnv, dc)
if err != nil {
return err
}
if totalFreeEcSlots < 1 {
return fmt.Errorf("no free ec shard slots. only %d left", totalFreeEcSlots)
}
racks := collectRacks(allEcNodes)
for _, c := range collections {
if err = balanceEcVolumes(commandEnv, c, allEcNodes, racks, applyBalancing); err != nil {
return err
}
}
if err := balanceEcRacks(commandEnv, racks, applyBalancing); err != nil {
return fmt.Errorf("balance ec racks: %v", err)
}
return nil
}