我正在尝试编写一个小型 http 服务器,以便以后使用 Google 的 Go 语言进行扩展。我在 Windows 上使用 Go(MinGw 编译版本)。
这在这种语言中很容易,因为它已经有了必要的包:
package main
import (
"http"
"io"
"os"
"fmt"
"strconv"
)
func FileTest(w http.ResponseWriter, req *http.Request) {
w.Header().Add("Content-Type", "image/jpeg")
w.Header().Add("Content-Disposition", "inline; filename=image.jpg")
inName := "d:\\googlego\\somepic.jpg";
inFile, inErr := os.OpenFile(inName, os.O_RDONLY, 0666);
if inErr == nil {
inBufLen := 16;
inBuf := make([]byte, inBufLen);
_, inErr := inFile.Read(inBuf);
for inErr == nil {
w.Write(inBuf)
_, inErr = inFile.Read(inBuf);
}
}
inErr = inFile.Close();
}
func MainPage(w http.ResponseWriter, req *http.Request) {
io.WriteString(w, "Hi, download here: <a href=\"/FileTest\">HERE</a>")
}
func main() {
fmt.Print("Port: ")
var hi int
fmt.Scanf("%d", &hi)
http.HandleFunc("/FileTest", FileTest)
http.HandleFunc("/", MainPage)
err := http.ListenAndServe("0.0.0.0:" + strconv.Itoa(hi), nil)
if err != nil {
fmt.Print(err)
fmt.Print((hi))
}
}
这将启动一个服务于主页和从图像下载的服务器。两者都工作得很好,我从 ab(Apache 基准测试)中获得了非常好的结果,最多 6 个并发线程:
> ab -n 10000 -c 6 http://localhost:8080/
Concurrency Level: 6
Time taken for tests: 1.678096 seconds
Complete requests: 10000
Percentage of the requests served within a certain time (ms)
50% 1
66% 1
75% 1
80% 1
90% 2
95% 2
98% 2
99% 2
100% 3 (longest request)
当并发级别设置得更高时,会发生这种情况:
>ab -n 1000 -c 7 http://localhost:8080/
Concurrency Level: 7
Time taken for tests: 10.239586 seconds
Complete requests: 1000
Percentage of the requests served within a certain time (ms)
50% 1
66% 2
75% 2
80% 3
90% 499
95% 505
98% 507
99% 507
100% 510 (longest request)
请注意,我这次只发出了 1'000 个请求,但仍然花费了将近 6 倍的时间。
两个基准测试甚至都没有请求该文件。
我对 Go 还不太了解,但似乎 Go 运行时没有创建足够的操作系统线程来放置 goroutine 或类似的东西?
编辑:我从 07.10.2011 下载了新的 r60.2。
现在情况变得更糟了:
>ab -c 7 -n 1000 http://localhost:8080/
Concurrency Level: 7
Time taken for tests: 12.622722 seconds
Complete requests: 1000
Percentage of the requests served within a certain time (ms)
50% 1
66% 1
75% 2
80% 2
90% 496
95% 503
98% 506
99% 506
100% 507 (longest request)