mirror of
https://github.com/go-gitea/gitea.git
synced 2024-12-05 09:49:37 +08:00
445e47b692
v1.1.0 has improved buffer pooling
63 lines
1.9 KiB
Go
Vendored
63 lines
1.9 KiB
Go
Vendored
package render
|
|
|
|
import (
|
|
"bytes"
|
|
)
|
|
|
|
// Pulled from the github.com/oxtoacart/bpool package (Apache licensed).
|
|
|
|
// SizedBufferPool implements a pool of bytes.Buffers in the form of a bounded
|
|
// channel. Buffers are pre-allocated to the requested size.
|
|
type SizedBufferPool struct {
|
|
c chan *bytes.Buffer
|
|
a int
|
|
}
|
|
|
|
// NewSizedBufferPool creates a new BufferPool bounded to the given size.
|
|
// size defines the number of buffers to be retained in the pool and alloc sets
|
|
// the initial capacity of new buffers to minimize calls to make().
|
|
//
|
|
// The value of alloc should seek to provide a buffer that is representative of
|
|
// most data written to the the buffer (i.e. 95th percentile) without being
|
|
// overly large (which will increase static memory consumption). You may wish to
|
|
// track the capacity of your last N buffers (i.e. using an []int) prior to
|
|
// returning them to the pool as input into calculating a suitable alloc value.
|
|
func NewSizedBufferPool(size int, alloc int) (bp *SizedBufferPool) {
|
|
return &SizedBufferPool{
|
|
c: make(chan *bytes.Buffer, size),
|
|
a: alloc,
|
|
}
|
|
}
|
|
|
|
// Get gets a Buffer from the SizedBufferPool, or creates a new one if none are
|
|
// available in the pool. Buffers have a pre-allocated capacity.
|
|
func (bp *SizedBufferPool) Get() (b *bytes.Buffer) {
|
|
select {
|
|
case b = <-bp.c:
|
|
// reuse existing buffer
|
|
default:
|
|
// create new buffer
|
|
b = bytes.NewBuffer(make([]byte, 0, bp.a))
|
|
}
|
|
return
|
|
}
|
|
|
|
// Put returns the given Buffer to the SizedBufferPool.
|
|
func (bp *SizedBufferPool) Put(b *bytes.Buffer) {
|
|
b.Reset()
|
|
|
|
// Release buffers over our maximum capacity and re-create a pre-sized
|
|
// buffer to replace it.
|
|
// Note that the cap(b.Bytes()) provides the capacity from the read off-set
|
|
// only, but as we've called b.Reset() the full capacity of the underlying
|
|
// byte slice is returned.
|
|
if cap(b.Bytes()) > bp.a {
|
|
b = bytes.NewBuffer(make([]byte, 0, bp.a))
|
|
}
|
|
|
|
select {
|
|
case bp.c <- b:
|
|
default: // Discard the buffer if the pool is full.
|
|
}
|
|
}
|