golang 使用pprof和go-torch做性能分析 - GO

软件开发过程中，项目上线并不是终点。上线后，还要对程序的取样分析运行情况，并重构现有的功能，让程序执行更高效更稳写。 golang的工具包内自带pprof功能，使找出程序中占内存和CPU较多的部分功能方便了不少。加上uber的火焰图，可视化显示，让我们在分析程序时更简单明了。

pprof有两个包用来分析程序一个是net/http/pprof另一个是runtime/pprof，net/http/pprof只是对runtime/pprof包进行封装并用http暴露出来，如下图源码所示：

使用net/http/pprof分析web服务

pprof分析web项目，非常的简单只需要导入包即可。

_ "net/http/pprof"

复制

编写一个小的web服务器

package main
import (
_  "net/http/pprof"
"net/http"
"time"
"math/rand"
"fmt"
)
var Count int64 = 0
func main() {
go calCount()
http<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">HandleFunc</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token string" style="box-sizing: border-box; list-style: inherit; color: rgb(126, 198, 153);">&quot;/test&quot;</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> test<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
http<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">HandleFunc</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token string" style="box-sizing: border-box; list-style: inherit; color: rgb(126, 198, 153);">&quot;/data&quot;</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> handlerData<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>

<span class="token literal-property property" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">err</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">:</span><span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">=</span> http<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">ListenAndServe</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token string" style="box-sizing: border-box; list-style: inherit; color: rgb(126, 198, 153);">&quot;:9909&quot;</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> nil <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
<span class="token keyword" style="box-sizing: border-box; list-style: inherit; color: rgb(204, 153, 205);">if</span> err <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">!=</span> nil <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span>
    <span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">panic</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>err<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span>

}
func handlerData(w http.ResponseWriter, r *http.Request) {
qUrl := r.URL
fmt.Println(qUrl)
fibRev := Fib()
var fib uint64
for i:= 0; i < 5000; i++ {
fib = fibRev()
fmt.Println("fib = ", fib)
}
str := RandomStr(RandomInt(100, 500))
str =  fmt.Sprintf("Fib = %d; String = %s", fib, str)
w.Write([]byte(str))
}
func test(w http.ResponseWriter, r http.Request) {
fibRev := Fib()
var fib uint64
index := Count
arr := make([]uint64, index)
var i int64
for ; i < index; i++ {
fib = fibRev()
arr[i] = fib
fmt.Println("fib = ", fib)
}
time.Sleep(time.Millisecond  500)
str :=  fmt.Sprintf("Fib = %v", arr)
w.Write([]byte(str))
}
func Fib() func() uint64 {
var x, y uint64 = 0, 1
return func() uint64 {
x, y = y, x + y
return x
}
}
var letterRunes = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890")
func RandomStr(num int) string {
seed := time.Now().UnixNano()
if seed <= 0 {
seed = time.Now().UnixNano()
}
rand.Seed(seed)
b := make([]rune, num)
for i := range b {
b[i] = letterRunes[rand.Intn(len(letterRunes))]
}
return string(b)
}
func RandomInt(min, max int) int {
rand.Seed(time.Now().UnixNano())
return rand.Intn(max - min + 1) + min
}
func calCount() {
timeInterval := time.Tick(time.Second)
<span class="token keyword" style="box-sizing: border-box; list-style: inherit; color: rgb(204, 153, 205);">for</span> <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span>
    select <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span>
    <span class="token keyword" style="box-sizing: border-box; list-style: inherit; color: rgb(204, 153, 205);">case</span> <span class="token literal-property property" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">i</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">:</span><span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">=</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">&lt;</span><span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">-</span> timeInterval<span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">:</span>
        Count <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">=</span> <span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">int64</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>i<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Second</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
    <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span>
<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span>

}

复制

web服务监听9909端口

web服务器有两个http方法 test：根据当前的秒数做斐波那契计算 data：做一个5000的斐波那契计算并返回一个随机的字符串

运行程序,通过访问 http://192.168.3.34:9909/debug/pprof/可以查看web版的profiles相关信息

这几个路径表示的是

/debug/pprof/profile：访问这个链接会自动进行 CPU profiling，持续 30s，并生成一个文件供下载

/debug/pprof/block：Goroutine阻塞事件的记录。默认每发生一次阻塞事件时取样一次。

/debug/pprof/goroutines：活跃Goroutine的信息的记录。仅在获取时取样一次。

/debug/pprof/heap：堆内存分配情况的记录。默认每分配512K字节时取样一次。

/debug/pprof/mutex: 查看争用互斥锁的持有者。

/debug/pprof/threadcreate: 系统线程创建情况的记录。仅在获取时取样一次。

除了这些golang为我提供了更多方便的方法，用于分析，下面我们来用命令去访问详细的信息

我们用wrk来访问我们的两个方法，这样我们的服务会处在高速运行状态，取样的结果会更准确

wrk -c 20 -t 5 -d 3m http://192.168.3.34:9909/data
wrk -c 20 -t 5 -d 3m http://192.168.3.34:9909/test

复制

分析CPU使用情况

使用命令分析CPU使用情况

go tool pprof httpdemo http://192.168.3.34:9909/debug/pprof/profile

复制

在默认情况下，Go语言的运行时系统会以100 Hz的的频率对CPU使用情况进行取样。也就是说每秒取样100次，即每10毫秒会取样一次。为什么使用这个频率呢？因为100 Hz既足够产生有用的数据，又不至于让系统产生停顿。并且100这个数上也很容易做换算，比如把总取样计数换算为每秒的取样数。实际上，这里所说的对CPU使用情况的取样就是对当前的Goroutine的堆栈上的程序计数器的取样。

默认的取样时间是30s 你可以通过-seconds 命令来指定取样时间。取样完成后会进入命令行状态：

可以输入help查看相关的命令.这里说几个常用的命令

top命令，输入top命令默认是返加前10的占用cpu的方法。当然人可以在命令后面加数字指定top数

list命令根据你的正则输出相关的方法.直接跟可选项o 会输出所有的方法。也可以指定方法名

如： handlerData方法占cpu的74.81%

web命令：以网页的形式展现：更直观的显示cpu的使用情况

分析内存使用情况

和分析cpu差不多使用命令

go tool pprof httpdemo http://192.168.3.34:9909/debug/pprof/heap

复制

默认情况下取样时只取当前内存使用情况，可以加可选命令alloc_objects，将从程序开始时的内存取样

go tool pprof -alloc_objects httpdemo http://192.168.3.34:9909/debug/pprof/heap

复制

和cpu的命令一样，top list web。不同的是这里显示的是内存使用情况而已。这里我就不演示了。

安装go-torch

还有更方便的工具就是uber的 go-torch了

安装很简单

go get github.com/uber/go-torch
cd $GOPATH/src/github.com/uber/go-torch
git clone https://github.com/brendangregg/FlameGraph.git

复制

然后运行FlameGraph下的拷贝 flamegraph.pl 到 /usr/local/bin

火焰图分析CPU

使用命令

go-torch -u http://192.168.3.34:9909  --seconds 60 -f cpu.svg

复制

会在当前目录下生成cpu.svg文件，使用浏览器打开

更直观的看到应用程序的问题。handlerData方法占用的cpu时间过长。然后就是去代码里分析并优化了。

火焰图分析内存

使用命令

go-torch  http://192.168.3.34:9909/debug/pprof/heap --colors mem  -f mem.svg

复制

会在当前目录下生成cpu.svg文件，使用浏览器打开

使用runtime/pprof分析项目

如果你的项目不是web服务，比如是rpc服务等，就要使用runtime/pprof。他提供了很多方法，有时间可以看一下源码

我写了一个简单的工具类。用于调用分析

package profapp
import (
"os"
"rrnc_im/lib/zaplogger"
"go.uber.org/zap"
"runtime/pprof"
"runtime"
)
func StartCpuProf() {
f, err := os.Create("cpu.prof")
if err != nil {
zaplogger.Error("create cpu profile file error: ", zap.Error(err))
return
}
if err := pprof.StartCPUProfile(f); err != nil {
zaplogger.Error("can not start cpu profile,  error: ", zap.Error(err))
f.Close()
}
}
func StopCpuProf() {
pprof.StopCPUProfile()
}
//--------Mem
func ProfGc() {
runtime.GC() // get up-to-date statistics
}
func SaveMemProf() {
f, err := os.Create("mem.prof")
if err != nil {
zaplogger.Error("create mem profile file error: ", zap.Error(err))
return
}
<span class="token keyword" style="box-sizing: border-box; list-style: inherit; color: rgb(204, 153, 205);">if</span> <span class="token literal-property property" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">err</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">:</span><span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">=</span> pprof<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">WriteHeapProfile</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>f<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">;</span> err <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">!=</span> nil <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span>
    zaplogger<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Error</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token string" style="box-sizing: border-box; list-style: inherit; color: rgb(126, 198, 153);">&quot;could not write memory profile: &quot;</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> zap<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Error</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>err<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span>
f<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Close</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>

}
// goroutine block
func SaveBlockProfile() {
f, err := os.Create("block.prof")
if err != nil {
zaplogger.Error("create mem profile file error: ", zap.Error(err))
return
}
<span class="token keyword" style="box-sizing: border-box; list-style: inherit; color: rgb(204, 153, 205);">if</span> <span class="token literal-property property" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">err</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">:</span><span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">=</span> pprof<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Lookup</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token string" style="box-sizing: border-box; list-style: inherit; color: rgb(126, 198, 153);">&quot;block&quot;</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">WriteTo</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>f<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> <span class="token number" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">0</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">;</span> err <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">!=</span> nil <span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span>
    zaplogger<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Error</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token string" style="box-sizing: border-box; list-style: inherit; color: rgb(126, 198, 153);">&quot;could not write block profile: &quot;</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> zap<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Error</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>err<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span>
f<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Close</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>

}

复制

在需要分析的方法内调用这些方法就可以比如我是用rpc开放了几个方法

type TestProf struct {
}
func (TestProf) StartCpuProAct(context.Context, im_test.TestRequest, *im_test.TestRequest) error {
profapp.StartCpuProf()
return nil
}
func (TestProf) StopCpuProfAct(context.Context, im_test.TestRequest, *im_test.TestRequest) error {
profapp.StopCpuProf()
return nil
}
func (TestProf) ProfGcAct(context.Context, im_test.TestRequest, *im_test.TestRequest) error {
profapp.ProfGc()
return nil
}
func (TestProf) SaveMemAct(context.Context, im_test.TestRequest, *im_test.TestRequest) error {
profapp.SaveMemProf()
return nil
}
func (TestProf) SaveBlockProfileAct(context.Context, im_test.TestRequest, *im_test.TestRequest) error {
profapp.SaveBlockProfile()
return nil
}

复制

调用

profTest.StartCpuProAct(context.TODO(), &im_test.TestRequest{})
time<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">Sleep</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>time<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span>Second <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">*</span> <span class="token number" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">30</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
profTest<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">StopCpuProfAct</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>context<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token constant" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">TODO</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">&amp;</span>im_test<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span>TestRequest<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>

profTest<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">SaveMemAct</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>context<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token constant" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">TODO</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">&amp;</span>im_test<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span>TestRequest<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span>
profTest<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token function" style="box-sizing: border-box; list-style: inherit; color: rgb(240, 141, 73);">SaveBlockProfileAct</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span>context<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span><span class="token constant" style="box-sizing: border-box; list-style: inherit; color: rgb(248, 197, 85);">TODO</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">(</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">,</span> <span class="token operator" style="box-sizing: border-box; list-style: inherit; color: rgb(103, 205, 204);">&amp;</span>im_test<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">.</span>TestRequest<span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">{</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">}</span><span class="token punctuation" style="box-sizing: border-box; list-style: inherit;">)</span></code></pre>

复制

思想是一样的，会在当前文件夹内导出profile文件。然后用火焰图去分析，就不能指定域名了，要指定文件

 go-torch  httpdemo cpu.prof 
 go-torch  httpdemo mem.prof

复制

本文参与腾讯云自媒体分享计划，分享自作者个人站点/博客。

原始发表：2018-07-30 ，如有侵权请联系 cloudcommunity@tencent.com 删除