opt: make channel buffered if necessary

connection_unix.go

@@ -40,8 +40,8 @@ type conn struct {
 	sa             unix.Sockaddr          // remote socket address
 	ctx            interface{}            // user-defined context
 	loop           *eventloop             // connected event-loop
-	buffer         []byte                 // reuse memory of inbound data as a temporary buffer
 	codec          ICodec                 // codec for TCP
+	buffer         []byte                 // reuse memory of inbound data as a temporary buffer
 	opened         bool                   // connection opened event fired
 	localAddr      net.Addr               // local addr
 	remoteAddr     net.Addr               // remote addr

gnet.go

@@ -23,6 +23,7 @@ package gnet
 
 import (
 	"net"
+	"runtime"
 	"strings"
 	"sync/atomic"
 	"time"
@@ -264,3 +265,17 @@ func sniffErrorAndLog(err error) {
 		logging.DefaultLogger.Errorf(err.Error())
 	}
 }
+
+// channelBuffer determines whether the channel should be a buffered channel to get the best performance.
+func channelBuffer(preset int) int {
+	// Use blocking channel if GOMAXPROCS=1.
+	// This switches context from sender to receiver immediately,
+	// which results in higher performance (under go1.5 at least).
+	if runtime.GOMAXPROCS(0) == 1 {
+		return 0
+	}
+
+	// Use non-blocking workerChan if GOMAXPROCS>1,
+	// since otherwise the sender might be dragged down if the receiver is CPU-bound.
+	return preset
+}

server_unix.go

@@ -235,7 +235,7 @@ func serve(eventHandler EventHandler, listener *listener, options *Options) erro
 	}
 
 	svr.cond = sync.NewCond(&sync.Mutex{})
-	svr.ticktock = make(chan time.Duration, 1)
+	svr.ticktock = make(chan time.Duration, channelBuffer(1))
 	svr.logger = logging.DefaultLogger
 	svr.codec = func() ICodec {
 		if options.Codec == nil {

server_windows.go

@@ -36,7 +36,7 @@ import (
 
 // commandBufferSize represents the buffer size of event-loop command channel on Windows.
 const (
-	commandBufferSize = 512
+	commandBufferSize = 128
 )
 
 var errCloseAllConns = errors.New("close all connections in event-loop")
@@ -86,7 +86,7 @@ func (svr *server) startListener() {
 func (svr *server) startEventLoops(numEventLoop int) {
 	for i := 0; i < numEventLoop; i++ {
 		el := &eventloop{
-			ch:                make(chan interface{}, commandBufferSize),
+			ch:                make(chan interface{}, channelBuffer(commandBufferSize)),
 			svr:               svr,
 			connections:       make(map[*stdConn]struct{}),
 			eventHandler:      svr.eventHandler,