Go HTTP Server bench from https://github.com/bitemyapp/FrameworkBenchmarks

http.go

package main

import (
  "encoding/json"
	"net/http"
	"runtime"
	"strconv"
)

type MessageStruct struct {
	Message string
}

func hello(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/javascript")
	j, _ := json.Marshal(&MessageStruct{"Hello, world"})
	w.Header().Set("Content-Length", strconv.Itoa(len(j)))
	w.Write(j)
}

func main() {
	runtime.GOMAXPROCS(runtime.NumCPU())
	http.HandleFunc("/json", hello)
	http.ListenAndServe(":8080", nil)
}

results.txt

tested with https://github.com/wg/wrk
parameters: wrk -t8 -c400 -r10m http://localhost:8080/json
(UPDATE: running wrk on _different_ machine than the http server)

Go 1.0.3:
Making 10000000 requests to http://HTTPTARGET:8080/json
  8 threads and 400 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     7.87ms    3.42ms 202.81ms   90.42%
    Req/Sec     5.99k   223.13     8.00k    97.96%
  10000010 requests in 3.30m, 1.30GB read
  Socket errors: connect 0, read 0, write 0, timeout 17
Requests/sec:  50458.87
Transfer/sec:      6.74MB

Go 1.1 (go version devel +3346bb37412c Fri Apr 05 13:43:18 2013 +1100 linux/amd64):
Making 10000000 requests to http://HTTPTARGET:8080/json
  8 threads and 400 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     1.61ms    1.02ms  10.60ms   81.10%
    Req/Sec    19.04k   443.99    21.00k    90.82%
  10000074 requests in 1.05m, 1.30GB read
  Socket errors: connect 0, read 0, write 0, timeout 143
Requests/sec: 158248.92
Transfer/sec:     21.13MB

Netty (from https://github.com/TechEmpower/FrameworkBenchmarks/tree/master/netty ):
Making 10000000 requests to http://HTTPTARGET:8080/
  8 threads and 400 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     1.29ms  697.34us  15.05ms   87.34%
    Req/Sec    21.91k   599.71    28.00k    82.05%
  10000048 requests in 0.93m, 1.68GB read
  Socket errors: connect 0, read 0, write 0, timeout 93
Requests/sec: 178662.24
Transfer/sec:     30.67MB