diff --git a/README.md b/README.md
index 151e34c4..5a8662d5 100644
--- a/README.md
+++ b/README.md
@@ -33,9 +33,8 @@ excellent [Performance](#performance), and is more suitable for microservice arc
 Also [Netpoll][Netpoll] provides a number of [Features](#features), and it is recommended
 to replace [net][net] in some RPC scenarios.
 
-We developed the RPC framework [Kitex][Kitex] and HTTP
-framework [Hertz][Hertz] (coming soon) based
-on [Netpoll][Netpoll], both with industry-leading performance.
+We developed the RPC framework [Kitex][Kitex] and HTTP framework [Hertz][Hertz]
+based on [Netpoll][Netpoll], both with industry-leading performance.
 
 [Examples][netpoll-examples] show how to build RPC client and server
 using [Netpoll][Netpoll].
@@ -73,7 +72,7 @@ In the RPC scenario, concurrency and timeout are necessary support items.
 We provide the [netpoll-benchmark][netpoll-benchmark] project to track and compare 
 the performance of [Netpoll][Netpoll] and other frameworks under different conditions for reference.
 
-More benchmarks reference [kitex-benchmark][kitex-benchmark] and [hertz-benchmark][hertz-benchmark] (open source soon).
+More benchmarks reference [kitex-benchmark][kitex-benchmark] and [hertz-benchmark][hertz-benchmark].
 
 ## Reference
 
diff --git a/README_CN.md b/README_CN.md
index a209f3ed..8e8d0bac 100644
--- a/README_CN.md
+++ b/README_CN.md
@@ -29,8 +29,7 @@ goroutine，大幅增加调度开销。此外，[net.Conn][net.Conn] 没有提
 同时，[Netpoll][Netpoll] 还提供了一些 [特性](#特性)，推荐在 RPC 设计中替代
 [net][net] 。
 
-基于 [Netpoll][Netpoll] 开发的 RPC 框架 [Kitex][Kitex] 和 HTTP
-框架 [Hertz][Hertz] (即将开源)，性能均业界领先。
+基于 [Netpoll][Netpoll] 开发的 RPC 框架 [Kitex][Kitex] 和 HTTP 框架 [Hertz][Hertz]，性能均业界领先。
 
 [范例][netpoll-examples] 展示了如何使用 [Netpoll][Netpoll]
 构建 RPC Client 和 Server。
@@ -66,7 +65,7 @@ goroutine，大幅增加调度开销。此外，[net.Conn][net.Conn] 没有提
 
 我们提供了 [netpoll-benchmark][netpoll-benchmark] 项目用来长期追踪和比较 [Netpoll][Netpoll] 与其他框架在不同情况下的性能数据以供参考。
 
-更多测试参考 [kitex-benchmark][kitex-benchmark] 和 [hertz-benchmark][hertz-benchmark] (即将开源)
+更多测试参考 [kitex-benchmark][kitex-benchmark] 和 [hertz-benchmark][hertz-benchmark]
 
 ## 参考
 
diff --git a/connection_onevent.go b/connection_onevent.go
index a4bcc286..6d875b41 100644
--- a/connection_onevent.go
+++ b/connection_onevent.go
@@ -54,32 +54,37 @@ type callbackNode struct {
 }
 
 // SetOnConnect set the OnConnect callback.
-func (on *onEvent) SetOnConnect(onConnect OnConnect) error {
+func (c *connection) SetOnConnect(onConnect OnConnect) error {
 	if onConnect != nil {
-		on.onConnectCallback.Store(onConnect)
+		c.onConnectCallback.Store(onConnect)
 	}
 	return nil
 }
 
 // SetOnRequest initialize ctx when setting OnRequest.
-func (on *onEvent) SetOnRequest(onRequest OnRequest) error {
-	if onRequest != nil {
-		on.onRequestCallback.Store(onRequest)
+func (c *connection) SetOnRequest(onRequest OnRequest) error {
+	if onRequest == nil {
+		return nil
+	}
+	c.onRequestCallback.Store(onRequest)
+	// fix: trigger OnRequest if there is already input data.
+	if !c.inputBuffer.IsEmpty() {
+		c.onRequest()
 	}
 	return nil
 }
 
 // AddCloseCallback adds a CloseCallback to this connection.
-func (on *onEvent) AddCloseCallback(callback CloseCallback) error {
+func (c *connection) AddCloseCallback(callback CloseCallback) error {
 	if callback == nil {
 		return nil
 	}
 	var cb = &callbackNode{}
 	cb.fn = callback
-	if pre := on.closeCallbacks.Load(); pre != nil {
+	if pre := c.closeCallbacks.Load(); pre != nil {
 		cb.pre = pre.(*callbackNode)
 	}
-	on.closeCallbacks.Store(cb)
+	c.closeCallbacks.Store(cb)
 	return nil
 }
 
@@ -203,6 +208,10 @@ func (c *connection) closeCallback(needLock bool) (err error) {
 	if needLock && !c.lock(processing) {
 		return nil
 	}
+	// If Close is called during OnPrepare, poll is not registered.
+	if c.closeBy(user) && c.operator.poll != nil {
+		c.operator.Control(PollDetach)
+	}
 	var latest = c.closeCallbacks.Load()
 	if latest == nil {
 		return nil
diff --git a/connection_reactor.go b/connection_reactor.go
index 6b621f72..c175fca0 100644
--- a/connection_reactor.go
+++ b/connection_reactor.go
@@ -41,10 +41,6 @@ func (c *connection) onHup(p Poll) error {
 // onClose means close by user.
 func (c *connection) onClose() error {
 	if c.closeBy(user) {
-		// If Close is called during OnPrepare, poll is not registered.
-		if c.operator.poll != nil {
-			c.operator.Control(PollDetach)
-		}
 		c.triggerRead()
 		c.triggerWrite(ErrConnClosed)
 		c.closeCallback(true)
@@ -157,7 +153,9 @@ func (c *connection) flush() error {
 	if err != nil {
 		return Exception(err, "when flush")
 	}
-
 	err = <-c.writeTrigger
-	return err
+	if err != nil {
+		return Exception(err, "when flush")
+	}
+	return nil
 }
diff --git a/net_polldesc.go b/net_polldesc.go
index 740ef444..b199372a 100644
--- a/net_polldesc.go
+++ b/net_polldesc.go
@@ -59,7 +59,7 @@ func (pd *pollDesc) WaitWrite(ctx context.Context) error {
 		pd.operator.poll = pollmanager.Pick()
 		err = pd.operator.Control(PollWritable)
 		if err != nil {
-			pd.operator.Control(PollDetach)
+			pd.detach()
 		}
 	})
 	if err != nil {
@@ -68,7 +68,7 @@ func (pd *pollDesc) WaitWrite(ctx context.Context) error {
 
 	select {
 	case <-ctx.Done():
-		pd.operator.Control(PollDetach)
+		pd.detach()
 		return mapErr(ctx.Err())
 	case <-pd.closeTrigger:
 		return Exception(ErrConnClosed, "by peer")
@@ -82,3 +82,8 @@ func (pd *pollDesc) WaitWrite(ctx context.Context) error {
 		}
 	}
 }
+
+func (pd *pollDesc) detach() {
+	pd.operator.Control(PollDetach)
+	pd.operator.unused()
+}
diff --git a/nocopy_linkbuffer_test.go b/nocopy_linkbuffer_test.go
index 9af49fb6..c581901b 100644
--- a/nocopy_linkbuffer_test.go
+++ b/nocopy_linkbuffer_test.go
@@ -327,6 +327,27 @@ func TestLinkBufferRefer(t *testing.T) {
 	Equal(t, buf.read.Len(), block8k-9)
 }
 
+func TestLinkBufferResetTail(t *testing.T) {
+	except := byte(1)
+
+	LinkBufferCap = 8
+	buf := NewLinkBuffer()
+
+	// 1. slice reader
+	buf.WriteByte(except)
+	buf.Flush()
+	r1, _ := buf.Slice(1)
+	fmt.Printf("1: %x\n", buf.flush.buf)
+	// 2. release & reset tail
+	buf.resetTail(LinkBufferCap)
+	buf.WriteByte(byte(2))
+	fmt.Printf("2: %x\n", buf.flush.buf)
+
+	// check slice reader
+	got, _ := r1.ReadByte()
+	Equal(t, got, except)
+}
+
 func TestWriteBuffer(t *testing.T) {
 	buf1 := NewLinkBuffer()
 	buf2 := NewLinkBuffer()
diff --git a/poll_default_linux.go b/poll_default_linux.go
index 2fbffbfb..49a170ff 100644
--- a/poll_default_linux.go
+++ b/poll_default_linux.go
@@ -109,6 +109,9 @@ func (p *defaultPoll) Wait() (err error) {
 func (p *defaultPoll) handler(events []epollevent) (closed bool) {
 	for i := range events {
 		var operator = *(**FDOperator)(unsafe.Pointer(&events[i].data))
+		if !operator.do() {
+			continue
+		}
 		// trigger or exit gracefully
 		if operator.FD == p.wop.FD {
 			// must clean trigger first
@@ -118,11 +121,10 @@ func (p *defaultPoll) handler(events []epollevent) (closed bool) {
 			if p.buf[0] > 0 {
 				syscall.Close(p.wop.FD)
 				syscall.Close(p.fd)
+				operator.done()
 				return true
 			}
-			continue
-		}
-		if !operator.do() {
+			operator.done()
 			continue
 		}
 
diff --git a/poll_manager.go b/poll_manager.go
index 3fded62e..9f23c777 100644
--- a/poll_manager.go
+++ b/poll_manager.go
@@ -49,7 +49,7 @@ type manager struct {
 // SetNumLoops will return error when set numLoops < 1
 func (m *manager) SetNumLoops(numLoops int) error {
 	if numLoops < 1 {
-		return fmt.Errorf("set invaild numLoops[%d]", numLoops)
+		return fmt.Errorf("set invalid numLoops[%d]", numLoops)
 	}
 
 	if numLoops < m.NumLoops {
diff --git a/poll_race_bsd.go b/poll_race_bsd.go
index 3b8171e8..39b2d7e6 100644
--- a/poll_race_bsd.go
+++ b/poll_race_bsd.go
@@ -82,12 +82,11 @@ func (p *defaultPoll) Wait() error {
 				atomic.StoreUint32(&p.trigger, 0)
 				continue
 			}
-			var operator *FDOperator
-			if tmp, ok := p.m.Load(fd); ok {
-				operator = tmp.(*FDOperator)
-			} else {
+			tmp, ok := p.m.Load(fd)
+			if !ok {
 				continue
 			}
+			operator := tmp.(*FDOperator)
 			if !operator.do() {
 				continue
 			}
diff --git a/poll_race_linux.go b/poll_race_linux.go
index 948d0133..85fdff6c 100644
--- a/poll_race_linux.go
+++ b/poll_race_linux.go
@@ -102,14 +102,9 @@ func (p *defaultPoll) Wait() (err error) {
 
 func (p *defaultPoll) handler(events []syscall.EpollEvent) (closed bool) {
 	for i := range events {
-		var operator *FDOperator
-		if tmp, ok := p.m.Load(int(events[i].Fd)); ok {
-			operator = tmp.(*FDOperator)
-		} else {
-			continue
-		}
+		var fd = int(events[i].Fd)
 		// trigger or exit gracefully
-		if operator.FD == p.wfd {
+		if fd == p.wfd {
 			// must clean trigger first
 			syscall.Read(p.wfd, p.buf)
 			atomic.StoreUint32(&p.trigger, 0)
@@ -121,6 +116,11 @@ func (p *defaultPoll) handler(events []syscall.EpollEvent) (closed bool) {
 			}
 			continue
 		}
+		tmp, ok := p.m.Load(fd)
+		if !ok {
+			continue
+		}
+		operator := tmp.(*FDOperator)
 		if !operator.do() {
 			continue
 		}
diff --git a/sys_exec.go b/sys_exec.go
index 33122adf..511a26fb 100644
--- a/sys_exec.go
+++ b/sys_exec.go
@@ -68,6 +68,7 @@ func writev(fd int, bs [][]byte, ivs []syscall.Iovec) (n int, err error) {
 	}
 	// syscall
 	r, _, e := syscall.RawSyscall(syscall.SYS_WRITEV, uintptr(fd), uintptr(unsafe.Pointer(&ivs[0])), uintptr(iovLen))
+	resetIovecs(bs, ivs[:iovLen])
 	if e != 0 {
 		return int(r), syscall.Errno(e)
 	}
@@ -83,6 +84,7 @@ func readv(fd int, bs [][]byte, ivs []syscall.Iovec) (n int, err error) {
 	}
 	// syscall
 	r, _, e := syscall.RawSyscall(syscall.SYS_READV, uintptr(fd), uintptr(unsafe.Pointer(&ivs[0])), uintptr(iovLen))
+	resetIovecs(bs, ivs[:iovLen])
 	if e != 0 {
 		return int(r), syscall.Errno(e)
 	}
@@ -98,15 +100,22 @@ func iovecs(bs [][]byte, ivs []syscall.Iovec) (iovLen int) {
 		if len(chunk) == 0 {
 			continue
 		}
-		iov := &syscall.Iovec{Base: &chunk[0]}
-		iov.SetLen(len(chunk))
-		// append
-		ivs[iovLen] = *iov
+		ivs[iovLen].Base = &chunk[0]
+		ivs[iovLen].SetLen(len(chunk))
 		iovLen++
 	}
 	return iovLen
 }
 
+func resetIovecs(bs [][]byte, ivs []syscall.Iovec) {
+	for i := 0; i < len(bs); i++ {
+		bs[i] = nil
+	}
+	for i := 0; i < len(ivs); i++ {
+		ivs[i].Base = nil
+	}
+}
+
 // Boolean to int.
 func boolint(b bool) int {
 	if b {
diff --git a/sys_sendmsg_bsd.go b/sys_sendmsg_bsd.go
index 263efb07..d605ae4d 100644
--- a/sys_sendmsg_bsd.go
+++ b/sys_sendmsg_bsd.go
@@ -36,6 +36,7 @@ func sendmsg(fd int, bs [][]byte, ivs []syscall.Iovec, zerocopy bool) (n int, er
 	}
 	// flags = syscall.MSG_DONTWAIT
 	r, _, e := syscall.RawSyscall(syscall.SYS_SENDMSG, uintptr(fd), uintptr(unsafe.Pointer(&msghdr)), uintptr(0))
+	resetIovecs(bs, ivs[:iovLen])
 	if e != 0 {
 		return int(r), syscall.Errno(e)
 	}
diff --git a/sys_sendmsg_linux.go b/sys_sendmsg_linux.go
index 86d7af92..5a849db2 100644
--- a/sys_sendmsg_linux.go
+++ b/sys_sendmsg_linux.go
@@ -45,6 +45,7 @@ func sendmsg(fd int, bs [][]byte, ivs []syscall.Iovec, zerocopy bool) (n int, er
 		flags = MSG_ZEROCOPY
 	}
 	r, _, e := syscall.RawSyscall(syscall.SYS_SENDMSG, uintptr(fd), uintptr(unsafe.Pointer(&msghdr)), flags)
+	resetIovecs(bs, ivs[:iovLen])
 	if e != 0 {
 		return int(r), syscall.Errno(e)
 	}