diff --git a/pkg/config/config.go b/pkg/config/config.go
index cf792191..e379d034 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -128,9 +128,9 @@ func init() {
 var Debug bool
 
 var (
-	SmallBufferSize  = 2 * 1024  // 2KB small buffer
-	MediumBufferSize = 8 * 1024  // 8KB medium buffer
-	LargeBufferSize  = 32 * 1024 // 32KB large buffer
+	SmallBufferSize  = 8 * 1024  // 8KB small buffer
+	MediumBufferSize = 32 * 1024 // 32KB medium buffer
+	LargeBufferSize  = 64 * 1024 // 64KB large buffer
 )
 
 var (
diff --git a/pkg/core/gvisortcpforwarder.go b/pkg/core/gvisortcpforwarder.go
index 1b4ca8ce..6efbb2cf 100644
--- a/pkg/core/gvisortcpforwarder.go
+++ b/pkg/core/gvisortcpforwarder.go
@@ -73,8 +73,8 @@ func TCPForwarder(s *stack.Stack, ctx context.Context) func(stack.TransportEndpo
 
 func WriteProxyInfo(conn net.Conn, id stack.TransportEndpointID) error {
 	var b bytes.Buffer
-	i := config.MPool.Get().([]byte)[:]
-	defer config.MPool.Put(i[:])
+	i := config.LPool.Get().([]byte)[:]
+	defer config.LPool.Put(i[:])
 	binary.BigEndian.PutUint16(i, id.LocalPort)
 	b.Write(i)
 	binary.BigEndian.PutUint16(i, id.RemotePort)
diff --git a/pkg/core/gvisortunendpoint.go b/pkg/core/gvisortunendpoint.go
index 3c0bf908..3b0b5ce9 100755
--- a/pkg/core/gvisortunendpoint.go
+++ b/pkg/core/gvisortunendpoint.go
@@ -50,16 +50,16 @@ func (h *gvisorTCPHandler) readFromTCPConnWriteToEndpoint(ctx context.Context, c
 		default:
 		}
 
-		buf := config.SPool.Get().([]byte)[:]
+		buf := config.LPool.Get().([]byte)[:]
 		read, err := tcpConn.Read(buf[:])
 		if err != nil {
 			log.Errorf("[TUN] Failed to read from tcp conn: %v", err)
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			return
 		}
 		if read == 0 {
 			log.Warnf("[TUN] Read from tcp conn length is %d", read)
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 		// Try to determine network protocol number, default zero.
@@ -73,7 +73,7 @@ func (h *gvisorTCPHandler) readFromTCPConnWriteToEndpoint(ctx context.Context, c
 			ipHeader, err := ipv4.ParseHeader(buf[:read])
 			if err != nil {
 				log.Errorf("Failed to parse IPv4 header: %v", err)
-				config.SPool.Put(buf[:])
+				config.LPool.Put(buf[:])
 				continue
 			}
 			ipProtocol = ipHeader.Protocol
@@ -84,7 +84,7 @@ func (h *gvisorTCPHandler) readFromTCPConnWriteToEndpoint(ctx context.Context, c
 			ipHeader, err := ipv6.ParseHeader(buf[:read])
 			if err != nil {
 				log.Errorf("Failed to parse IPv6 header: %s", err.Error())
-				config.SPool.Put(buf[:])
+				config.LPool.Put(buf[:])
 				continue
 			}
 			ipProtocol = ipHeader.NextHeader
@@ -92,7 +92,7 @@ func (h *gvisorTCPHandler) readFromTCPConnWriteToEndpoint(ctx context.Context, c
 			dst = ipHeader.Dst
 		} else {
 			log.Debugf("[TUN-GVISOR] Unknown packet")
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 
@@ -111,7 +111,7 @@ func (h *gvisorTCPHandler) readFromTCPConnWriteToEndpoint(ctx context.Context, c
 			ReserveHeaderBytes: 0,
 			Payload:            buffer.MakeWithData(buf[:read]),
 		})
-		config.SPool.Put(buf[:])
+		config.LPool.Put(buf[:])
 		sniffer.LogPacket("[gVISOR] ", sniffer.DirectionRecv, protocol, pkt)
 		endpoint.InjectInbound(protocol, pkt)
 		pkt.DecRef()
diff --git a/pkg/core/tcphandler.go b/pkg/core/tcphandler.go
index b4532269..5df5ee70 100644
--- a/pkg/core/tcphandler.go
+++ b/pkg/core/tcphandler.go
@@ -78,11 +78,11 @@ func (h *fakeUdpHandler) Handle(ctx context.Context, tcpConn net.Conn) {
 		default:
 		}
 
-		buf := config.SPool.Get().([]byte)[:]
+		buf := config.LPool.Get().([]byte)[:]
 		dgram, err := readDatagramPacketServer(tcpConn, buf[:])
 		if err != nil {
 			log.Errorf("[TCP] %s -> %s : %v", tcpConn.RemoteAddr(), tcpConn.LocalAddr(), err)
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			return
 		}
 
@@ -90,7 +90,7 @@ func (h *fakeUdpHandler) Handle(ctx context.Context, tcpConn net.Conn) {
 		src, _, err = util.ParseIP(dgram.Data[:dgram.DataLength])
 		if err != nil {
 			log.Errorf("[TCP] Unknown packet")
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 		value, loaded := h.routeMapTCP.LoadOrStore(src.String(), tcpConn)
diff --git a/pkg/core/tunhandler.go b/pkg/core/tunhandler.go
index 5c14a17e..b99f7c64 100644
--- a/pkg/core/tunhandler.go
+++ b/pkg/core/tunhandler.go
@@ -96,24 +96,24 @@ type Device struct {
 
 func (d *Device) readFromTun() {
 	for {
-		buf := config.SPool.Get().([]byte)[:]
+		buf := config.LPool.Get().([]byte)[:]
 		n, err := d.tun.Read(buf[:])
 		if err != nil {
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			log.Errorf("[TUN] Failed to read from tun: %v", err)
 			util.SafeWrite(d.chExit, err)
 			return
 		}
 		if n == 0 {
 			log.Errorf("[TUN] Read packet length 0")
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 
 		src, dst, err := util.ParseIP(buf[:n])
 		if err != nil {
 			log.Errorf("[TUN] Unknown packet")
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 
@@ -130,7 +130,7 @@ func (d *Device) readFromTun() {
 func (d *Device) writeToTun() {
 	for e := range d.tunOutbound {
 		_, err := d.tun.Write(e.data[:e.length])
-		config.SPool.Put(e.data[:])
+		config.LPool.Put(e.data[:])
 		if err != nil {
 			util.SafeWrite(d.chExit, err)
 			return
@@ -278,17 +278,17 @@ func (p *Peer) sendErr(err error) {
 
 func (p *Peer) readFromConn() {
 	for {
-		buf := config.SPool.Get().([]byte)[:]
+		buf := config.LPool.Get().([]byte)[:]
 		n, from, err := p.conn.ReadFrom(buf[:])
 		if err != nil {
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			p.sendErr(err)
 			return
 		}
 
 		src, dst, err := util.ParseIP(buf[:n])
 		if err != nil {
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			log.Errorf("[TUN] Unknown packet: %v", err)
 			continue
 		}
@@ -316,7 +316,7 @@ func (p *Peer) readFromTCPConn() {
 		src, dst, err := util.ParseIP(packet.Data)
 		if err != nil {
 			log.Errorf("[TUN] Unknown packet")
-			config.SPool.Put(packet.Data[:])
+			config.LPool.Put(packet.Data[:])
 			continue
 		}
 		u := &udpElem{
@@ -335,7 +335,7 @@ func (p *Peer) routePeer() {
 		if routeToAddr := p.routeMapUDP.RouteTo(e.dst); routeToAddr != nil {
 			log.Debugf("[UDP] Find UDP route to dst: %s -> %s", e.dst, routeToAddr)
 			_, err := p.conn.WriteTo(e.data[:e.length], routeToAddr)
-			config.SPool.Put(e.data[:])
+			config.LPool.Put(e.data[:])
 			if err != nil {
 				p.sendErr(err)
 				return
@@ -344,7 +344,7 @@ func (p *Peer) routePeer() {
 			log.Debugf("[TCP] Find TCP route to dst: %s -> %s", e.dst.String(), conn.(net.Conn).RemoteAddr())
 			dgram := newDatagramPacket(e.data[:e.length])
 			err := dgram.Write(conn.(net.Conn))
-			config.SPool.Put(e.data[:])
+			config.LPool.Put(e.data[:])
 			if err != nil {
 				log.Errorf("[TCP] udp-tun %s <- %s : %s", conn.(net.Conn).RemoteAddr(), dgram.Addr(), err)
 				p.sendErr(err)
@@ -367,7 +367,7 @@ func (p *Peer) routeTUN() {
 		if addr := p.routeMapUDP.RouteTo(e.dst); addr != nil {
 			log.Debugf("[TUN] Find UDP route to dst: %s -> %s", e.dst, addr)
 			_, err := p.conn.WriteTo(e.data[:e.length], addr)
-			config.SPool.Put(e.data[:])
+			config.LPool.Put(e.data[:])
 			if err != nil {
 				log.Debugf("[TUN] Failed wirte to route dst: %s -> %s", e.dst, addr)
 				p.sendErr(err)
@@ -377,7 +377,7 @@ func (p *Peer) routeTUN() {
 			log.Debugf("[TUN] Find TCP route to dst: %s -> %s", e.dst.String(), conn.(net.Conn).RemoteAddr())
 			dgram := newDatagramPacket(e.data[:e.length])
 			err := dgram.Write(conn.(net.Conn))
-			config.SPool.Put(e.data[:])
+			config.LPool.Put(e.data[:])
 			if err != nil {
 				log.Errorf("[TUN] Failed to write TCP %s <- %s : %s", conn.(net.Conn).RemoteAddr(), dgram.Addr(), err)
 				p.sendErr(err)
@@ -385,7 +385,7 @@ func (p *Peer) routeTUN() {
 			}
 		} else {
 			log.Errorf("[TUN] No route for src: %s -> dst: %s, drop it", e.src, e.dst)
-			config.SPool.Put(e.data[:])
+			config.LPool.Put(e.data[:])
 		}
 	}
 }
diff --git a/pkg/core/tunhandlerclient.go b/pkg/core/tunhandlerclient.go
index ab5cdfa2..bcfb71f5 100644
--- a/pkg/core/tunhandlerclient.go
+++ b/pkg/core/tunhandlerclient.go
@@ -87,7 +87,7 @@ func transportTunClient(ctx context.Context, tunInbound <-chan *DataElem, tunOut
 				continue
 			}
 			_, err := packetConn.WriteTo(e.data[:e.length], remoteAddr)
-			config.SPool.Put(e.data[:])
+			config.LPool.Put(e.data[:])
 			if err != nil {
 				util.SafeWrite(errChan, errors.Wrap(err, fmt.Sprintf("failed to write packet to remote %s", remoteAddr)))
 				return
@@ -97,10 +97,10 @@ func transportTunClient(ctx context.Context, tunInbound <-chan *DataElem, tunOut
 
 	go func() {
 		for {
-			buf := config.SPool.Get().([]byte)[:]
+			buf := config.LPool.Get().([]byte)[:]
 			n, _, err := packetConn.ReadFrom(buf[:])
 			if err != nil {
-				config.SPool.Put(buf[:])
+				config.LPool.Put(buf[:])
 				util.SafeWrite(errChan, errors.Wrap(err, fmt.Sprintf("failed to read packet from remote %s", remoteAddr)))
 				return
 			}
@@ -146,15 +146,15 @@ func (d *ClientDevice) SetTunInboundHandler(handler func(tunInbound <-chan *Data
 
 func (d *ClientDevice) readFromTun() {
 	for {
-		buf := config.SPool.Get().([]byte)[:]
+		buf := config.LPool.Get().([]byte)[:]
 		n, err := d.tun.Read(buf[:])
 		if err != nil {
 			util.SafeWrite(d.chExit, err)
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			return
 		}
 		if n == 0 {
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 
@@ -163,7 +163,7 @@ func (d *ClientDevice) readFromTun() {
 		src, dst, err = util.ParseIP(buf[:n])
 		if err != nil {
 			log.Debugf("[TUN-GVISOR] Unknown packet: %v", err)
-			config.SPool.Put(buf[:])
+			config.LPool.Put(buf[:])
 			continue
 		}
 		log.Tracef("[TUN-RAW] SRC: %s, DST: %s, Length: %d", src.String(), dst, n)
@@ -174,7 +174,7 @@ func (d *ClientDevice) readFromTun() {
 func (d *ClientDevice) writeToTun() {
 	for e := range d.tunOutbound {
 		_, err := d.tun.Write(e.data[:e.length])
-		config.SPool.Put(e.data[:])
+		config.LPool.Put(e.data[:])
 		if err != nil {
 			util.SafeWrite(d.chExit, err)
 			return
diff --git a/pkg/core/udpovertcp.go b/pkg/core/udpovertcp.go
index 9bb7dab4..60859543 100644
--- a/pkg/core/udpovertcp.go
+++ b/pkg/core/udpovertcp.go
@@ -61,8 +61,8 @@ func readDatagramPacketServer(r io.Reader, b []byte) (*datagramPacket, error) {
 }
 
 func (addr *datagramPacket) Write(w io.Writer) error {
-	buf := config.MPool.Get().([]byte)[:]
-	defer config.MPool.Put(buf[:])
+	buf := config.LPool.Get().([]byte)[:]
+	defer config.LPool.Put(buf[:])
 	binary.BigEndian.PutUint16(buf[:2], uint16(len(addr.Data)))
 	n := copy(buf[2:], addr.Data)
 	_, err := w.Write(buf[:n+2])
diff --git a/pkg/tun/tun.go b/pkg/tun/tun.go
index a43313cb..e507b56c 100644
--- a/pkg/tun/tun.go
+++ b/pkg/tun/tun.go
@@ -84,8 +84,8 @@ type tunConn struct {
 
 func (c *tunConn) Read(b []byte) (n int, err error) {
 	offset := device.MessageTransportHeaderSize
-	buf := config.MPool.Get().([]byte)[:]
-	defer config.MPool.Put(buf[:])
+	buf := config.LPool.Get().([]byte)[:]
+	defer config.LPool.Put(buf[:])
 
 	var size int
 	size, err = c.ifce.Read(buf[:], offset)
@@ -102,8 +102,8 @@ func (c *tunConn) Write(b []byte) (n int, err error) {
 	if len(b) < device.MessageTransportHeaderSize {
 		return 0, err
 	}
-	buf := config.MPool.Get().([]byte)[:]
-	defer config.MPool.Put(buf[:])
+	buf := config.LPool.Get().([]byte)[:]
+	defer config.LPool.Put(buf[:])
 
 	copy(buf[device.MessageTransportOffsetContent:], b)