From e0b56528fc42972f4116a85553f382f5b95bd2bc Mon Sep 17 00:00:00 2001
From: v2ray <admin@v2ray.com>
Date: Sun, 10 Jan 2016 10:50:36 +0100
Subject: [PATCH] leverage sync.Pool for allocation boost

---
 common/alloc/buffer.go | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/common/alloc/buffer.go b/common/alloc/buffer.go
index 66357cfd9..553b4db5a 100644
--- a/common/alloc/buffer.go
+++ b/common/alloc/buffer.go
@@ -1,5 +1,9 @@
 package alloc
 
+import (
+	"sync"
+)
+
 // Buffer is a recyclable allocation of a byte array. Buffer.Release() recycles
 // the buffer into an internal buffer pool, in order to recreate a buffer more
 // quickly.
@@ -69,15 +73,16 @@ func (b *Buffer) Write(data []byte) (int, error) {
 }
 
 type bufferPool struct {
-	chain        chan []byte
-	bufferSize   int
-	buffers2Keep int
+	chain     chan []byte
+	allocator *sync.Pool
 }
 
 func newBufferPool(bufferSize, poolSize int) *bufferPool {
 	pool := &bufferPool{
-		chain:      make(chan []byte, poolSize),
-		bufferSize: bufferSize,
+		chain: make(chan []byte, poolSize),
+		allocator: &sync.Pool{
+			New: func() interface{} { return make([]byte, bufferSize) },
+		},
 	}
 	for i := 0; i < poolSize; i++ {
 		pool.chain <- make([]byte, bufferSize)
@@ -90,7 +95,7 @@ func (p *bufferPool) allocate() *Buffer {
 	select {
 	case b = <-p.chain:
 	default:
-		b = make([]byte, p.bufferSize)
+		b = p.allocator.Get().([]byte)
 	}
 	return &Buffer{
 		head:  b,
@@ -103,6 +108,7 @@ func (p *bufferPool) free(buffer *Buffer) {
 	select {
 	case p.chain <- buffer.head:
 	default:
+		p.allocator.Put(buffer.head)
 	}
 }