remove buffer pool in favor of Go 1.9 concurrent GC

common/buf/buffer_pool.go

@@ -1,10 +1,7 @@
 package buf
 
 import (
-	"runtime"
 	"sync"
-
-	"v2ray.com/core/common/platform"
 )
 
 // Pool provides functionality to generate and recycle buffers on demand.
@@ -45,79 +42,11 @@ func (p *SyncPool) Free(buffer *Buffer) {
 	}
 }
 
-// BufferPool is a Pool that utilizes an internal cache.
-type BufferPool struct {
-	chain chan []byte
-	sub   Pool
-}
-
-// NewBufferPool creates a new BufferPool with given buffer size, and internal cache size.
-func NewBufferPool(bufferSize, poolSize uint32) *BufferPool {
-	pool := &BufferPool{
-		chain: make(chan []byte, poolSize),
-		sub:   NewSyncPool(bufferSize),
-	}
-	for i := uint32(0); i < poolSize; i++ {
-		pool.chain <- make([]byte, bufferSize)
-	}
-	return pool
-}
-
-// Allocate implements Pool.Allocate().
-func (p *BufferPool) Allocate() *Buffer {
-	select {
-	case b := <-p.chain:
-		return &Buffer{
-			v:    b,
-			pool: p,
-		}
-	default:
-		return p.sub.Allocate()
-	}
-}
-
-// Free implements Pool.Free().
-func (p *BufferPool) Free(buffer *Buffer) {
-	if buffer.v == nil {
-		return
-	}
-	select {
-	case p.chain <- buffer.v:
-	default:
-		p.sub.Free(buffer)
-	}
-}
-
 const (
 	// Size of a regular buffer.
 	Size = 2 * 1024
-
-	poolSizeEnvKey = "v2ray.buffer.size"
 )
 
 var (
-	mediumPool Pool
+	mediumPool Pool = NewSyncPool(Size)
 )
-
-func getDefaultPoolSize() int {
-	switch runtime.GOARCH {
-	case "amd64", "386":
-		return 20
-	default:
-		return 5
-	}
-}
-
-func init() {
-	f := platform.EnvFlag{
-		Name:    poolSizeEnvKey,
-		AltName: platform.NormalizeEnvName(poolSizeEnvKey),
-	}
-	size := f.GetValueAsInt(getDefaultPoolSize())
-	if size > 0 {
-		totalByteSize := uint32(size) * 1024 * 1024
-		mediumPool = NewBufferPool(Size, totalByteSize/Size)
-	} else {
-		mediumPool = NewSyncPool(Size)
-	}
-}