allow access to -smuxbuf parameter for handling HOLB

README.md

@@ -23,33 +23,33 @@
 
 > *Disclaimer: kcptun maintains a single website — [github.com/xtaci/kcptun](https://github.com/xtaci/kcptun). Any websites other than [github.com/xtaci/kcptun](https://github.com/xtaci/kcptun) are not endorsed by xtaci.*
 
-> *KCP discussion QQ group: 364933586, KCP integration, tuning, network transmission and related technical discussions.*
-
 ### QuickStart
 
 Increase the number of open files on your server, as:
 
 `ulimit -n 65535`, or write it in `~/.bashrc`.
 
-Increase the OS UDP buffers to improve performance, as:
+Suggested `sysctl.conf` parameters for better handling of UDP packets:
 
 ```
-net.core.rmem_max=26214400
+net.core.rmem_max=26214400 // BDP - bandwidth delay product
 net.core.rmem_default=26214400
+net.core.wmem_max=26214400
+net.core.wmem_default=26214400
+net.core.netdev_max_backlog=2048 // proportional to -rcvwnd
 ```
 
 You can also increase the per-socket buffer by adding parameter(default 4MB):
 ```
 -sockbuf 16777217
 ```
-increasing this would work for most of the old model CPUs.
-
+for **slow processors**, increasing this buffer is **CRITICAL** to receive packets properly.
 
 Download a corresponding one from precompiled [Releases](https://github.com/xtaci/kcptun/releases).
 
 ```
-KCP Client: ./client_darwin_amd64 -r "KCP_SERVER_IP:4000" -l ":8388" -mode fast2
-KCP Server: ./server_linux_amd64 -t "TARGET_IP:8388" -l ":4000" -mode fast2
+KCP Client: ./client_darwin_amd64 -r "KCP_SERVER_IP:4000" -l ":8388" -mode fast3 -nocomp -autoexpire 900 -sockbuf 16777217 -dscp 46
+KCP Server: ./server_linux_amd64 -t "TARGET_IP:8388" -l ":4000" -mode fast3 -nocomp -sockbuf 16777217 -dscp 46
 ```
 The above commands will establish port forwarding channel for 8388/tcp as:
 
@@ -92,7 +92,10 @@ All precompiled releases are genereated from `build-release.sh` script.
 
 > *fast3 > fast2 > fast > normal > default*
 
+#### HOLB
 
+Since streams are multiplexed into a single physical channel, head of line blocking may appear under certain circumstances, by
+increasing `-smuxbuf` to a larger value (default 4MB) may mitigate this problem, obviously this will costs more memory.
 
 ### Expert Tuning Guide
 
@@ -339,7 +342,6 @@ The parameters below **MUST** be **IDENTICAL** on **BOTH** side:
 1. http://http2.github.io/ -- What is HTTP/2?
 1. http://www.lartc.org/ -- Linux Advanced Routing & Traffic Control
 1. https://en.wikipedia.org/wiki/Noisy-channel_coding_theorem -- Noisy channel coding theorem
-1. https://play.google.com/store/apps/details?id=com.k17game.k3 -- Battle Zone - Earth 2048, an online strategy game using kcp.
 
 ### Donate 
 
@@ -350,3 +352,5 @@ via Ethereum(ETH): Address: 0x2e4b43ab3d0983da282592571eef61ae5e60f726 , Or scan
 via WeChat
 
 <img src="wechat_donate.jpg" alt="kcptun" height="120px" /> 
+
+（注意：我没有任何社交网站的账号，请小心骗子。）

client/config.go

@@ -28,6 +28,7 @@ type Config struct {
 	Resend       int    `json:"resend"`
 	NoCongestion int    `json:"nc"`
 	SockBuf      int    `json:"sockbuf"`
+	SmuxBuf      int    `json:"smuxbuf"`
 	KeepAlive    int    `json:"keepalive"`
 	Log          string `json:"log"`
 	SnmpLog      string `json:"snmplog"`

client/main.go

@@ -209,6 +209,11 @@ func main() {
 			Value: 4194304, // socket buffer size in bytes
 			Usage: "per-socket buffer in bytes",
 		},
+		cli.IntFlag{
+			Name:  "smuxbuf",
+			Value: 4194304,
+			Usage: "the overall de-mux buffer in bytes",
+		},
 		cli.IntFlag{
 			Name:  "keepalive",
 			Value: 10, // nat keepalive interval in seconds
@@ -262,6 +267,7 @@ func main() {
 		config.Resend = c.Int("resend")
 		config.NoCongestion = c.Int("nc")
 		config.SockBuf = c.Int("sockbuf")
+		config.SmuxBuf = c.Int("smuxbuf")
 		config.KeepAlive = c.Int("keepalive")
 		config.Log = c.String("log")
 		config.SnmpLog = c.String("snmplog")
@@ -342,6 +348,7 @@ func main() {
 		log.Println("acknodelay:", config.AckNodelay)
 		log.Println("dscp:", config.DSCP)
 		log.Println("sockbuf:", config.SockBuf)
+		log.Println("smuxbuf:", config.SmuxBuf)
 		log.Println("keepalive:", config.KeepAlive)
 		log.Println("conn:", config.Conn)
 		log.Println("autoexpire:", config.AutoExpire)
@@ -351,7 +358,7 @@ func main() {
 		log.Println("quiet:", config.Quiet)
 
 		smuxConfig := smux.DefaultConfig()
-		smuxConfig.MaxReceiveBuffer = config.SockBuf
+		smuxConfig.MaxReceiveBuffer = config.SmuxBuf
 		smuxConfig.KeepAliveInterval = time.Duration(config.KeepAlive) * time.Second
 
 		createConn := func() (*smux.Session, error) {

go.mod

@@ -0,0 +1,17 @@
+module github.com/xtaci/kcptun
+
+require (
+	github.com/golang/snappy v0.0.1
+	github.com/klauspost/cpuid v1.2.0 // indirect
+	github.com/klauspost/reedsolomon v1.9.1 // indirect
+	github.com/pkg/errors v0.8.1
+	github.com/templexxx/cpufeat v0.0.0-20180724012125-cef66df7f161 // indirect
+	github.com/templexxx/xor v0.0.0-20181023030647-4e92f724b73b // indirect
+	github.com/tjfoc/gmsm v1.0.1 // indirect
+	github.com/urfave/cli v1.20.0
+	github.com/xtaci/kcp-go v5.1.3+incompatible
+	github.com/xtaci/smux v1.1.2
+	golang.org/x/crypto v0.0.0-20190320223903-b7391e95e576
+	golang.org/x/net v0.0.0-20190324223953-e3b2ff56ed87 // indirect
+	golang.org/x/sys v0.0.0-20190322080309-f49334f85ddc // indirect
+)

go.sum

@@ -0,0 +1,38 @@
+github.com/golang/snappy v0.0.1 h1:Qgr9rKW7uDUkrbSmQeiDsGa8SjGyCOGtuasMWwvp2P4=
+github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
+github.com/klauspost/cpuid v1.2.0 h1:NMpwD2G9JSFOE1/TJjGSo5zG7Yb2bTe7eq1jH+irmeE=
+github.com/klauspost/cpuid v1.2.0/go.mod h1:Pj4uuM528wm8OyEC2QMXAi2YiTZ96dNQPGgoMS4s3ek=
+github.com/klauspost/reedsolomon v1.9.1 h1:kYrT1MlR4JH6PqOpC+okdb9CDTcwEC/BqpzK4WFyXL8=
+github.com/klauspost/reedsolomon v1.9.1/go.mod h1:CwCi+NUr9pqSVktrkN+Ondf06rkhYZ/pcNv7fu+8Un4=
+github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/templexxx/cpufeat v0.0.0-20180724012125-cef66df7f161 h1:89CEmDvlq/F7SJEOqkIdNDGJXrQIhuIx9D2DBXjavSU=
+github.com/templexxx/cpufeat v0.0.0-20180724012125-cef66df7f161/go.mod h1:wM7WEvslTq+iOEAMDLSzhVuOt5BRZ05WirO+b09GHQU=
+github.com/templexxx/xor v0.0.0-20181023030647-4e92f724b73b h1:mnG1fcsIB1d/3vbkBak2MM0u+vhGhlQwpeimUi7QncM=
+github.com/templexxx/xor v0.0.0-20181023030647-4e92f724b73b/go.mod h1:5XA7W9S6mni3h5uvOC75dA3m9CCCaS83lltmc0ukdi4=
+github.com/tjfoc/gmsm v1.0.1 h1:R11HlqhXkDospckjZEihx9SW/2VW0RgdwrykyWMFOQU=
+github.com/tjfoc/gmsm v1.0.1/go.mod h1:XxO4hdhhrzAd+G4CjDqaOkd0hUzmtPR/d3EiBBMn/wc=
+github.com/urfave/cli v1.20.0 h1:fDqGv3UG/4jbVl/QkFwEdddtEDjh/5Ov6X+0B/3bPaw=
+github.com/urfave/cli v1.20.0/go.mod h1:70zkFmudgCuE/ngEzBv17Jvp/497gISqfk5gWijbERA=
+github.com/xtaci/kcp-go v5.0.7+incompatible/go.mod h1:bN6vIwHQbfHaHtFpEssmWsN45a+AZwO7eyRCmEIbtvE=
+github.com/xtaci/kcp-go v5.1.1+incompatible h1:A6zXUGblo98vosfEdaHcy0cTBZKY2dByJxICuaV+L5g=
+github.com/xtaci/kcp-go v5.1.1+incompatible/go.mod h1:bN6vIwHQbfHaHtFpEssmWsN45a+AZwO7eyRCmEIbtvE=
+github.com/xtaci/kcp-go v5.1.2+incompatible h1:UafCgw2Yk3QOf8MRm8jYEWJt1l4J61BgLpMsROkJQxo=
+github.com/xtaci/kcp-go v5.1.2+incompatible/go.mod h1:bN6vIwHQbfHaHtFpEssmWsN45a+AZwO7eyRCmEIbtvE=
+github.com/xtaci/kcp-go v5.1.3+incompatible h1:s96+ulBrZlxk4DPRPgEGPBV8o55kYKKFVivDwVgZNcA=
+github.com/xtaci/kcp-go v5.1.3+incompatible/go.mod h1:bN6vIwHQbfHaHtFpEssmWsN45a+AZwO7eyRCmEIbtvE=
+github.com/xtaci/smux v1.1.1 h1:ZyIo9XHuHkAeENzHR8yGWC+6xUSCTeP2tPTRE8mnLvc=
+github.com/xtaci/smux v1.1.1/go.mod h1:f+nYm6SpuHMy/SH0zpbvAFHT1QoMcgLOsWcFip5KfPw=
+github.com/xtaci/smux v1.1.2 h1:AeAzHKqvDeFEcicL9Q06LTjIVW2I55iooUbpDRGHth4=
+github.com/xtaci/smux v1.1.2/go.mod h1:f+nYm6SpuHMy/SH0zpbvAFHT1QoMcgLOsWcFip5KfPw=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190320223903-b7391e95e576 h1:aUX/1G2gFSs4AsJJg2cL3HuoRhCSCz733FE5GUSuaT4=
+golang.org/x/crypto v0.0.0-20190320223903-b7391e95e576/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20190320064053-1272bf9dcd53 h1:kcXqo9vE6fsZY5X5Rd7R1l7fTgnWaDCVmln65REefiE=
+golang.org/x/net v0.0.0-20190320064053-1272bf9dcd53/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190324223953-e3b2ff56ed87 h1:yh5/K199RObPR6zqVBYf+AyJuweAqx+fOe9s3cekn1Y=
+golang.org/x/net v0.0.0-20190324223953-e3b2ff56ed87/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190321052220-f7bb7a8bee54/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190322080309-f49334f85ddc/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

server/config.go

@@ -25,6 +25,7 @@ type Config struct {
 	Resend       int    `json:"resend"`
 	NoCongestion int    `json:"nc"`
 	SockBuf      int    `json:"sockbuf"`
+	SmuxBuf      int    `json:"smuxbuf"`
 	KeepAlive    int    `json:"keepalive"`
 	Log          string `json:"log"`
 	SnmpLog      string `json:"snmplog"`

server/main.go

@@ -62,7 +62,7 @@ func newCompStream(conn net.Conn) *compStream {
 func handleMux(conn io.ReadWriteCloser, config *Config) {
 	// stream multiplex
 	smuxConfig := smux.DefaultConfig()
-	smuxConfig.MaxReceiveBuffer = config.SockBuf
+	smuxConfig.MaxReceiveBuffer = config.SmuxBuf
 	smuxConfig.KeepAliveInterval = time.Duration(config.KeepAlive) * time.Second
 
 	mux, err := smux.Server(conn, smuxConfig)
@@ -219,6 +219,11 @@ func main() {
 			Value: 4194304, // socket buffer size in bytes
 			Usage: "per-socket buffer in bytes",
 		},
+		cli.IntFlag{
+			Name:  "smuxbuf",
+			Value: 4194304,
+			Usage: "the overall de-mux buffer in bytes",
+		},
 		cli.IntFlag{
 			Name:  "keepalive",
 			Value: 10, // nat keepalive interval in seconds
@@ -273,6 +278,7 @@ func main() {
 		config.Resend = c.Int("resend")
 		config.NoCongestion = c.Int("nc")
 		config.SockBuf = c.Int("sockbuf")
+		config.SmuxBuf = c.Int("smuxbuf")
 		config.KeepAlive = c.Int("keepalive")
 		config.Log = c.String("log")
 		config.SnmpLog = c.String("snmplog")
@@ -352,6 +358,7 @@ func main() {
 		log.Println("acknodelay:", config.AckNodelay)
 		log.Println("dscp:", config.DSCP)
 		log.Println("sockbuf:", config.SockBuf)
+		log.Println("smuxbuf:", config.SmuxBuf)
 		log.Println("keepalive:", config.KeepAlive)
 		log.Println("snmplog:", config.SnmpLog)
 		log.Println("snmpperiod:", config.SnmpPeriod)