diff --git a/mempool/mempool.go b/mempool/mempool.go
index 8b865062..4100c658 100644
--- a/mempool/mempool.go
+++ b/mempool/mempool.go
@@ -17,8 +17,6 @@ type MemPool struct {
 }
 
 // New .
-//
-//go:norace
 func New(bufSize, freeSize int) Allocator {
 	if bufSize <= 0 {
 		bufSize = 64
@@ -45,8 +43,6 @@ func New(bufSize, freeSize int) Allocator {
 }
 
 // Malloc .
-//
-//go:norace
 func (mp *MemPool) Malloc(size int) []byte {
 	var ret []byte
 	if size > mp.freeSize {
@@ -65,8 +61,6 @@ func (mp *MemPool) Malloc(size int) []byte {
 }
 
 // Realloc .
-//
-//go:norace
 func (mp *MemPool) Realloc(buf []byte, size int) []byte {
 	if size <= cap(buf) {
 		return buf[:size]
@@ -87,26 +81,22 @@ func (mp *MemPool) Realloc(buf []byte, size int) []byte {
 }
 
 // Append .
-//
-//go:norace
 func (mp *MemPool) Append(buf []byte, more ...byte) []byte {
 	return append(buf, more...)
 }
 
 // AppendString .
-//
-//go:norace
 func (mp *MemPool) AppendString(buf []byte, more string) []byte {
 	return append(buf, more...)
 }
 
 // Free .
-//
-//go:norace
 func (mp *MemPool) Free(buf []byte) {
-	mp.incrFree(buf)
-	if cap(buf) > mp.freeSize {
-		return
+	if buf != nil && cap(buf) > 0 {
+		mp.incrFree(buf)
+		if cap(buf) > mp.freeSize {
+			return
+		}
+		mp.pool.Put(&buf)
 	}
-	mp.pool.Put(&buf)
 }
diff --git a/nbhttp/body.go b/nbhttp/body.go
index 72c7e615..c409dc4b 100644
--- a/nbhttp/body.go
+++ b/nbhttp/body.go
@@ -24,6 +24,7 @@ type BodyReader struct {
 	left    int      // num of byte left
 	buffers [][]byte // buffers that storage HTTP body
 	engine  *Engine  // allocator that manages buffers
+	closed  bool
 }
 
 // Read reads body bytes to p, returns the num of bytes read and error.
@@ -56,13 +57,17 @@ func (br *BodyReader) Read(p []byte) (int, error) {
 //
 //go:norace
 func (br *BodyReader) Close() error {
+	if br.closed {
+		return nil
+	}
+	br.closed = true
 	if br.buffers != nil {
 		for _, b := range br.buffers {
 			br.engine.BodyAllocator.Free(b)
 		}
 	}
-	*br = emptyBodyReader
-	bodyReaderPool.Put(br)
+	// *br = emptyBodyReader
+	// bodyReaderPool.Put(br)
 	return nil
 }
 
diff --git a/nbhttp/body_test.go b/nbhttp/body_test.go
index 7d4ae59c..90d3ae45 100644
--- a/nbhttp/body_test.go
+++ b/nbhttp/body_test.go
@@ -60,6 +60,7 @@ func TestBodyReader(t *testing.T) {
 	if !bytes.Equal(allBytes, body1) {
 		t.Fatalf("!bytes.Equal(allBytes, body1)")
 	}
+	br1.Close()
 
 	br2 := newBR()
 	body2 := make([]byte, len(allBytes))
@@ -72,4 +73,5 @@ func TestBodyReader(t *testing.T) {
 	if !bytes.Equal(allBytes, body2) {
 		t.Fatalf("!bytes.Equal(allBytes, body2)")
 	}
+	br2.Close()
 }
diff --git a/nbhttp/processor.go b/nbhttp/processor.go
index f3064184..a4b19a8a 100644
--- a/nbhttp/processor.go
+++ b/nbhttp/processor.go
@@ -49,6 +49,8 @@ func releaseRequest(req *http.Request, retainHTTPBody bool) {
 					// do not release the body
 				} else {
 					br.Close()
+					*br = emptyBodyReader
+					bodyReaderPool.Put(br)
 				}
 			} else if !retainHTTPBody {
 				req.Body.Close()
@@ -74,6 +76,8 @@ func releaseClientResponse(res *http.Response) {
 		if res.Body != nil {
 			br := res.Body.(*BodyReader)
 			br.Close()
+			*br = emptyBodyReader
+			bodyReaderPool.Put(br)
 		}
 		*res = emptyClientResponse
 		clientResponsePool.Put(res)