diff --git a/internal/caches/storage_file.go b/internal/caches/storage_file.go
index 484b71f..cbd390f 100644
--- a/internal/caches/storage_file.go
+++ b/internal/caches/storage_file.go
@@ -803,9 +803,9 @@ func (this *FileStorage) decodeFile(path string) (*Item, error) {
 
 	// URL
 	if urlSize > 0 {
-		data := utils.BytePool1024.Get()
+		data := utils.BytePool1k.Get()
 		result, ok, err := this.readN(fp, data, int(urlSize))
-		utils.BytePool1024.Put(data)
+		utils.BytePool1k.Put(data)
 		if err != nil {
 			return nil, err
 		}
@@ -942,7 +942,8 @@ func (this *FileStorage) hotLoop() {
 			size = len(result) / 10
 		}
 
-		var buf = make([]byte, 32*1024)
+		var buf = utils.BytePool16k.Get()
+		defer utils.BytePool16k.Put(buf)
 		for _, item := range result[:size] {
 			reader, err := this.openReader(item.Key, false, false)
 			if err != nil {
diff --git a/internal/nodes/client_listener.go b/internal/nodes/client_listener.go
index 8aa0d1a..b11017e 100644
--- a/internal/nodes/client_listener.go
+++ b/internal/nodes/client_listener.go
@@ -37,17 +37,12 @@ func (this *ClientListener) IsTLS() bool {
 
 func (this *ClientListener) Accept() (net.Conn, error) {
 	// 限制并发连接数
-	var isOk = false
 	var limiter = sharedConnectionsLimiter
 	limiter.Ack()
-	defer func() {
-		if !isOk {
-			limiter.Release()
-		}
-	}()
 
 	conn, err := this.rawListener.Accept()
 	if err != nil {
+		limiter.Release()
 		return nil, err
 	}
 
@@ -62,11 +57,11 @@ func (this *ClientListener) Accept() (net.Conn, error) {
 			}
 
 			_ = conn.Close()
+			limiter.Release()
 			return this.Accept()
 		}
 	}
 
-	isOk = true
 	return NewClientConn(conn, this.isTLS, this.quickClose, limiter), nil
 }
 
diff --git a/internal/nodes/http_request.go b/internal/nodes/http_request.go
index 03a5843..40a4363 100644
--- a/internal/nodes/http_request.go
+++ b/internal/nodes/http_request.go
@@ -28,12 +28,6 @@ import (
 // 环境变量
 var HOSTNAME, _ = os.Hostname()
 
-// byte pool
-var bytePool256b = utils.NewBytePool(20480, 256)
-var bytePool1k = utils.NewBytePool(20480, 1024)
-var bytePool32k = utils.NewBytePool(20480, 32*1024)
-var bytePool128k = utils.NewBytePool(20480, 128*1024)
-
 // errors
 var errWritingToClient = errors.New("writing to client error")
 
@@ -1303,19 +1297,16 @@ func (this *HTTPRequest) addError(err error) {
 
 // 计算合适的buffer size
 func (this *HTTPRequest) bytePool(contentLength int64) *utils.BytePool {
-	if contentLength <= 0 {
-		return bytePool1k
-	}
-	if contentLength < 1024 { // 1K
-		return bytePool256b
+	if contentLength < 8192 { // 8K
+		return utils.BytePool1k
 	}
 	if contentLength < 32768 { // 32K
-		return bytePool1k
+		return utils.BytePool4k
 	}
-	if contentLength < 1048576 { // 1M
-		return bytePool32k
+	if contentLength < 131072 { // 128K
+		return utils.BytePool16k
 	}
-	return bytePool128k
+	return utils.BytePool32k
 }
 
 // 检查是否可以忽略错误
diff --git a/internal/nodes/http_request_cache.go b/internal/nodes/http_request_cache.go
index 715efe1..f2b3261 100644
--- a/internal/nodes/http_request_cache.go
+++ b/internal/nodes/http_request_cache.go
@@ -194,13 +194,14 @@ func (this *HTTPRequest) doCacheRead(useStale bool) (shouldStop bool) {
 	}
 
 	// 准备Buffer
-	buf := bytePool32k.Get()
+	var pool = this.bytePool(reader.BodySize())
+	var buf = pool.Get()
 	defer func() {
-		bytePool32k.Put(buf)
+		pool.Put(buf)
 	}()
 
 	// 读取Header
-	headerBuf := []byte{}
+	var headerBuf = []byte{}
 	err = reader.ReadHeader(buf, func(n int) (goNext bool, err error) {
 		headerBuf = append(headerBuf, buf[:n]...)
 		for {
diff --git a/internal/nodes/http_request_page.go b/internal/nodes/http_request_page.go
index e7abc54..bfe57e4 100644
--- a/internal/nodes/http_request_page.go
+++ b/internal/nodes/http_request_page.go
@@ -68,11 +68,11 @@ func (this *HTTPRequest) doPage(status int) (shouldStop bool) {
 						this.writer.Prepare(stat.Size(), status)
 						this.writer.WriteHeader(status)
 					}
-					buf := bytePool1k.Get()
+					buf := utils.BytePool1k.Get()
 					_, err = utils.CopyWithFilter(this.writer, fp, buf, func(p []byte) []byte {
 						return []byte(this.Format(string(p)))
 					})
-					bytePool1k.Put(buf)
+					utils.BytePool1k.Put(buf)
 					if err != nil {
 						if !this.canIgnore(err) {
 							remotelogs.Warn("HTTP_REQUEST_PAGE", "write to client failed: "+err.Error())
diff --git a/internal/nodes/http_request_shutdown.go b/internal/nodes/http_request_shutdown.go
index b9d260a..c767138 100644
--- a/internal/nodes/http_request_shutdown.go
+++ b/internal/nodes/http_request_shutdown.go
@@ -64,11 +64,11 @@ func (this *HTTPRequest) doShutdown() {
 			this.processResponseHeaders(http.StatusOK)
 			this.writer.WriteHeader(http.StatusOK)
 		}
-		buf := bytePool1k.Get()
+		buf := utils.BytePool1k.Get()
 		_, err = utils.CopyWithFilter(this.writer, fp, buf, func(p []byte) []byte {
 			return []byte(this.Format(string(p)))
 		})
-		bytePool1k.Put(buf)
+		utils.BytePool1k.Put(buf)
 		if err != nil {
 			if !this.canIgnore(err) {
 				remotelogs.Warn("HTTP_REQUEST_SHUTDOWN", "write to client failed: "+err.Error())
diff --git a/internal/nodes/http_request_utils.go b/internal/nodes/http_request_utils.go
index fa44f1b..955de7c 100644
--- a/internal/nodes/http_request_utils.go
+++ b/internal/nodes/http_request_utils.go
@@ -2,12 +2,10 @@ package nodes
 
 import (
 	"crypto/rand"
-	"crypto/tls"
 	"fmt"
 	teaconst "github.com/TeaOSLab/EdgeNode/internal/const"
 	"github.com/TeaOSLab/EdgeNode/internal/utils"
 	"io"
-	"net"
 	"net/http"
 	"strconv"
 	"strings"
@@ -153,14 +151,5 @@ func httpRequestNextId() string {
 	}
 
 	// timestamp + requestId + nodeId
-	return strconv.FormatInt(unixTime, 10) + strconv.Itoa(int(atomic.AddInt32(&httpRequestId, 1))) + teaconst.NodeIdString
-}
-
-// 检查连接是否为TLS连接
-func httpIsTLSConn(conn net.Conn) bool {
-	if conn == nil {
-		return false
-	}
-	_, ok := conn.(*tls.Conn)
-	return ok
+	return strconv.FormatInt(unixTime, 10) + teaconst.NodeIdString + strconv.Itoa(int(atomic.AddInt32(&httpRequestId, 1)))
 }
diff --git a/internal/nodes/http_request_websocket.go b/internal/nodes/http_request_websocket.go
index d235904..68bc58f 100644
--- a/internal/nodes/http_request_websocket.go
+++ b/internal/nodes/http_request_websocket.go
@@ -3,6 +3,7 @@ package nodes
 import (
 	"errors"
 	"github.com/TeaOSLab/EdgeNode/internal/goman"
+	"github.com/TeaOSLab/EdgeNode/internal/utils"
 	"io"
 	"net/http"
 	"net/url"
@@ -66,7 +67,8 @@ func (this *HTTPRequest) doWebsocket() {
 	}()
 
 	goman.New(func() {
-		buf := make([]byte, 4*1024) // TODO 使用内存池
+		var buf = utils.BytePool4k.Get()
+		defer utils.BytePool4k.Put(buf)
 		for {
 			n, err := originConn.Read(buf)
 			if n > 0 {
diff --git a/internal/nodes/listener_tcp.go b/internal/nodes/listener_tcp.go
index 6f43087..089060b 100644
--- a/internal/nodes/listener_tcp.go
+++ b/internal/nodes/listener_tcp.go
@@ -7,6 +7,7 @@ import (
 	"github.com/TeaOSLab/EdgeNode/internal/goman"
 	"github.com/TeaOSLab/EdgeNode/internal/remotelogs"
 	"github.com/TeaOSLab/EdgeNode/internal/stats"
+	"github.com/TeaOSLab/EdgeNode/internal/utils"
 	"github.com/pires/go-proxyproto"
 	"net"
 	"strings"
@@ -112,9 +113,9 @@ func (this *TCPListener) handleConn(conn net.Conn) error {
 
 	// 从源站读取
 	goman.New(func() {
-		originBuffer := bytePool32k.Get()
+		originBuffer := utils.BytePool16k.Get()
 		defer func() {
-			bytePool32k.Put(originBuffer)
+			utils.BytePool16k.Put(originBuffer)
 		}()
 		for {
 			n, err := originConn.Read(originBuffer)
@@ -138,9 +139,9 @@ func (this *TCPListener) handleConn(conn net.Conn) error {
 	})
 
 	// 从客户端读取
-	clientBuffer := bytePool32k.Get()
+	clientBuffer := utils.BytePool16k.Get()
 	defer func() {
-		bytePool32k.Put(clientBuffer)
+		utils.BytePool16k.Put(clientBuffer)
 	}()
 	for {
 		n, err := conn.Read(clientBuffer)
diff --git a/internal/nodes/listener_udp.go b/internal/nodes/listener_udp.go
index 448738c..0f5aec7 100644
--- a/internal/nodes/listener_udp.go
+++ b/internal/nodes/listener_udp.go
@@ -190,9 +190,9 @@ func NewUDPConn(server *serverconfigs.ServerConfig, addr net.Addr, proxyConn *ne
 	}
 
 	goman.New(func() {
-		buffer := bytePool32k.Get()
+		buffer := utils.BytePool4k.Get()
 		defer func() {
-			bytePool32k.Put(buffer)
+			utils.BytePool4k.Put(buffer)
 		}()
 
 		for {
diff --git a/internal/utils/byte_pool.go b/internal/utils/byte_pool.go
index 60b87d2..7078179 100644
--- a/internal/utils/byte_pool.go
+++ b/internal/utils/byte_pool.go
@@ -1,16 +1,25 @@
 package utils
 
-var BytePool1024 = NewBytePool(20480, 1024)
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/goman"
+	"github.com/iwind/TeaGo/Tea"
+	"time"
+)
 
-// pool for get byte slice
+var BytePool1k = NewBytePool(20480, 1024)
+var BytePool4k = NewBytePool(20480, 4*1024)
+var BytePool16k = NewBytePool(40960, 16*1024)
+var BytePool32k = NewBytePool(20480, 32*1024)
+
+// BytePool pool for get byte slice
 type BytePool struct {
-	c      chan []byte
-	length int
-
-	lastSize int
+	c       chan []byte
+	maxSize int
+	length  int
+	hasNew  bool
 }
 
-// 创建新对象
+// NewBytePool 创建新对象
 func NewBytePool(maxSize, length int) *BytePool {
 	if maxSize <= 0 {
 		maxSize = 1024
@@ -18,24 +27,47 @@ func NewBytePool(maxSize, length int) *BytePool {
 	if length <= 0 {
 		length = 128
 	}
-	pool := &BytePool{
-		c:      make(chan []byte, maxSize),
-		length: length,
+	var pool = &BytePool{
+		c:       make(chan []byte, maxSize),
+		maxSize: maxSize,
+		length:  length,
 	}
+
+	pool.init()
+
 	return pool
 }
 
-// 获取一个新的byte slice
+// 初始化
+func (this *BytePool) init() {
+	var ticker = time.NewTicker(2 * time.Minute)
+	if Tea.IsTesting() {
+		ticker = time.NewTicker(5 * time.Second)
+	}
+	goman.New(func() {
+		for range ticker.C {
+			if this.hasNew {
+				this.hasNew = false
+				continue
+			}
+
+			this.Purge()
+		}
+	})
+}
+
+// Get 获取一个新的byte slice
 func (this *BytePool) Get() (b []byte) {
 	select {
 	case b = <-this.c:
 	default:
 		b = make([]byte, this.length)
+		this.hasNew = true
 	}
 	return
 }
 
-// 放回一个使用过的byte slice
+// Put 放回一个使用过的byte slice
 func (this *BytePool) Put(b []byte) {
 	if cap(b) != this.length {
 		return
@@ -47,7 +79,30 @@ func (this *BytePool) Put(b []byte) {
 	}
 }
 
-// 当前的数量
+// Length 单个字节slice长度
+func (this *BytePool) Length() int {
+	return this.length
+}
+
+// Size 当前的数量
 func (this *BytePool) Size() int {
 	return len(this.c)
 }
+
+// Purge 清理
+func (this *BytePool) Purge() {
+	// 1%
+	var count = len(this.c) / 100
+	if count == 0 {
+		return
+	}
+
+Loop:
+	for i := 0; i < count; i++ {
+		select {
+		case <-this.c:
+		default:
+			break Loop
+		}
+	}
+}
diff --git a/internal/utils/byte_pool_test.go b/internal/utils/byte_pool_test.go
index 8076065..0d305e6 100644
--- a/internal/utils/byte_pool_test.go
+++ b/internal/utils/byte_pool_test.go
@@ -27,6 +27,26 @@ func TestNewBytePool(t *testing.T) {
 	a.IsTrue(len(pool.c) == 5)
 }
 
+func TestBytePool_Memory(t *testing.T) {
+	var stat1 = &runtime.MemStats{}
+	runtime.ReadMemStats(stat1)
+
+	var pool = NewBytePool(20480, 32*1024)
+	for i := 0; i < 20480; i++ {
+		pool.Put(make([]byte, 32*1024))
+	}
+
+	//pool.Purge()
+
+	//time.Sleep(60 * time.Second)
+
+	runtime.GC()
+
+	var stat2 = &runtime.MemStats{}
+	runtime.ReadMemStats(stat2)
+	t.Log((stat2.HeapInuse-stat1.HeapInuse)/1024/1024, "MB,", pool.Size(), "slices")
+}
+
 func BenchmarkBytePool_Get(b *testing.B) {
 	runtime.GOMAXPROCS(1)
 
diff --git a/internal/waf/action_block.go b/internal/waf/action_block.go
index 2add6a5..d3e14c6 100644
--- a/internal/waf/action_block.go
+++ b/internal/waf/action_block.go
@@ -64,7 +64,6 @@ func (this *BlockAction) Perform(waf *WAF, group *RuleGroup, set *RuleSet, reque
 		timeout = 60 // 默认封锁60秒
 	}
 
-
 	SharedIPBlackList.RecordIP(IPTypeAll, this.Scope, request.WAFServerId(), request.WAFRemoteIP(), time.Now().Unix()+int64(timeout), waf.Id, group.Id, set.Id)
 
 	if writer != nil {
@@ -99,8 +98,9 @@ func (this *BlockAction) Perform(waf *WAF, group *RuleGroup, set *RuleSet, reque
 					}
 				}
 
-				buf := make([]byte, 1024)
+				buf := utils.BytePool1k.Get()
 				_, _ = io.CopyBuffer(writer, resp.Body, buf)
+				utils.BytePool1k.Put(buf)
 			} else {
 				path := this.URL
 				if !filepath.IsAbs(this.URL) {
diff --git a/internal/waf/checkpoints/request_headers_test.go b/internal/waf/checkpoints/request_headers_test.go
new file mode 100644
index 0000000..83d29b8
--- /dev/null
+++ b/internal/waf/checkpoints/request_headers_test.go
@@ -0,0 +1,33 @@
+// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package checkpoints
+
+import (
+	"net/http"
+	"runtime"
+	"sort"
+	"strings"
+	"testing"
+)
+
+func BenchmarkRequestHeadersCheckpoint_RequestValue(b *testing.B) {
+	runtime.GOMAXPROCS(1)
+
+	var header = http.Header{
+		"Content-Type":    []string{"keep-alive"},
+		"User-Agent":      []string{"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36"},
+		"Accept-Encoding": []string{"gzip, deflate, br"},
+		"Referer":         []string{"https://goedge.cn/"},
+	}
+
+	for i := 0; i < b.N; i++ {
+		var headers = []string{}
+		for k, v := range header {
+			for _, subV := range v {
+				headers = append(headers, k+": "+subV)
+			}
+		}
+		sort.Strings(headers)
+		_ = strings.Join(headers, "\n")
+	}
+}