tcp performance

client.go

package main

import (
	"flag"
	"fmt"
	"net"
	"os"
	"strings"
	"sync/atomic"
	"time"
)

func main() {
	flag.Parse()

	parts := strings.Split(targetAddr, "://")
	if parts[0][0:3] != "tcp" || len(parts) != 2 {
		panic("")
	}

	addr, err := net.ResolveTCPAddr("tcp", parts[1])
	if err != nil {
		fmt.Fprintf(os.Stderr, "net.ResolveTCPAddr() %v\n", err)
		os.Exit(3)
	}

	list_of_counters := make([]*uint64, concurrency)
	for i := 0; i < concurrency; i++ {
		c := uint64(0)
		list_of_counters[i] = &c
		go connect(addr, &c)
	}

	fmt.Printf("[*] Connecting to %q\n", addr.String())
	for {
		time.Sleep(1 * time.Second)
		sum := uint64(0)
		for i := 0; i < concurrency; i++ {
			v := atomic.LoadUint64(list_of_counters[i])
			atomic.AddUint64(list_of_counters[i], -v)
			sum += v
		}
		fmt.Printf("%.3foMiB\n", float64(sum)/1024.0/1024.0)
	}
}

func connect(addr *net.TCPAddr, c *uint64) {
	for {
		conn, err := net.DialTCP("tcp", nil, addr)
		if err != nil {
			fmt.Fprintf(os.Stderr, "net.DialTCP() %v\n", err)
			time.Sleep(1 * time.Second)
			continue
		}

		conn.SetReadBuffer(128*1024)
		conn.SetWriteBuffer(128*1024)

		go writeForever(conn)

		buf := make([]byte, 1024*16)
		for {
			reqLen, err := conn.Read(buf)
			if err != nil {
				fmt.Fprintf(os.Stderr, "conn.Read() %v\n", err)
				break
			}
			atomic.AddUint64(c, uint64(reqLen))
		}
		conn.Close()
		time.Sleep(1 * time.Second)
	}
}

func writeForever(conn net.Conn) {
	buf := make([]byte, 16*1024)
	for {
		_, err := conn.Write(buf[:])
		if err != nil {
			fmt.Fprintf(os.Stderr, "conn.Write() %v\n", err)
			break
		}
	}
	conn.Close()
}

var (
	targetAddr  string
	concurrency int
)

func init() {
	flag.StringVar(&targetAddr, "t", "tcp://127.0.0.1:8181", "Target to connect to")
	flag.IntVar(&concurrency, "c", 1, "Number of parallel connections")
}

server.go

package main

import (
	"flag"
	"fmt"
	"net"
	"os"
	"strings"
)

func main() {
	flag.Parse()

	parts := strings.Split(listenAddr, "://")
	if parts[0][0:3] != "tcp" || len(parts) != 2 {
		panic("")
	}

	addr, err := net.ResolveTCPAddr("tcp", parts[1])
	if err != nil {
		fmt.Fprintf(os.Stderr, "net.ResolveTCPAddr() %v\n", err)
		os.Exit(3)
	}

	srv, err := net.ListenTCP("tcp", addr)
	if err != nil {
		fmt.Fprintf(os.Stderr, "net.ListenTCP() %v\n", err)
		os.Exit(3)
	}

	fmt.Printf("[*] Bound to %q\n", addr)
	for {
		conn, err := srv.Accept()
		if err != nil {
			fmt.Fprintf(os.Stderr, "srv.Accept() %v\n", err)
			continue
		}

		go handle(conn.(*net.TCPConn))
	}
}

func handle(conn *net.TCPConn) {
	buf := make([]byte, 1024*16)

	conn.SetReadBuffer(128*1024)
	conn.SetWriteBuffer(128*1024)

	for {
		reqLen, err := conn.Read(buf)
		if err != nil {
			fmt.Fprintf(os.Stderr, "conn.Read() %v\n", err)
			break
		}

		_, err = conn.Write(buf[:reqLen])
		if err != nil {
			fmt.Fprintf(os.Stderr, "conn.Write() %v\n", err)
			break
		}
	}

	conn.Close()
}

var (
	listenAddr string
)

func init() {
	flag.StringVar(&listenAddr, "l", "tcp://0.0.0.0:8181", "Bind to")
}