為golang程式使用pprof遠程查看httpserver運行堆棧,cpu耗時等資訊

這是一個建立於 的文章，其中的資訊可能已經有所發展或是發生改變。

pprof是個神馬玩意兒？

pprof - manual page for pprof (part of gperftools)

是gperftools工具的一部分

gperftools又是啥？

These tools are for use by developers so that they can create more robust applications. Especially of use to those developing multi-threaded applications in C++ with templates. Includes TCMalloc, heap-checker, heap-profiler and cpu-profiler.

一個效能分析的工具，可以查看堆棧、cpu資訊等等。

 

在golang中如何使用呢？下面就來看看。

 

1. 在一個httpserver中，只需要一行代碼

 

package mainimport ("flag""log""net/http"_ "net/http/pprof""sync""time")func main() {flag.Parse()//這裡實現了遠程擷取pprof資料的介面go func() {log.Println(http.ListenAndServe("localhost:6060", nil))}()var wg sync.WaitGroupwg.Add(10)for i := 0; i < 10; i++ {go work(&wg)}wg.Wait()// Wait to see the global run queue deplete.time.Sleep(3 * time.Second)}func work(wg *sync.WaitGroup) {time.Sleep(time.Second)var counter intfor i := 0; i < 1e10; i++ {time.Sleep(time.Millisecond * 100)counter++}wg.Done()}

2.編譯運行這個程式

go build trace_example.go

./trace_example

 

3. 通過瀏覽器訪問

http://localhost:6060/debug/pprof/

能夠查看到程式的overview

 

 

 

4.你也可以通過終端命令查看

Then use the pprof tool to look at the heap profile:

go tool pprof http://localhost:6060/debug/pprof/heap

Or to look at a 30-second CPU profile:

go tool pprof http://localhost:6060/debug/pprof/profile

Or to look at the goroutine blocking profile:

go tool pprof http://localhost:6060/debug/pprof/block

qpzhang@qpzhangdeMac-mini:~/gocode $go tool pprof http://localhost:6060/debug/pprof/profileRead http://localhost:6060/debug/pprof/symbolGathering CPU profile from http://localhost:6060/debug/pprof/profile?seconds=30 for 30 seconds to  /var/folders/2l/195zcc1n0sn2wjfjwf9hl9d80000gn/T/mmBnpdkv0DBe patient...Wrote profile to /var/folders/2l/195zcc1n0sn2wjfjwf9hl9d80000gn/T/mmBnpdkv0DWelcome to pprof!  For help, type 'help'.(pprof) top10Total: 9 samples       6  66.7%  66.7%        6  66.7% runtime.mach_semaphore_wait       1  11.1%  77.8%        1  11.1% runtime.kevent       1  11.1%  88.9%        1  11.1% runtime.mach_semaphore_signal       1  11.1% 100.0%        1  11.1% runtime.mach_semaphore_timedwait       0   0.0% 100.0%        7  77.8% System       0   0.0% 100.0%        1  11.1% notetsleep       0   0.0% 100.0%        1  11.1% ready       0   0.0% 100.0%        2  22.2% runtime.gosched0       0   0.0% 100.0%        1  11.1% runtime.mach_semrelease       0   0.0% 100.0%        1  11.1% runtime.notetsleepg(pprof) webTotal: 9 samplesLoading web page file:////var/folders/2l/195zcc1n0sn2wjfjwf9hl9d80000gn/T/SlFUZhzBDB.0.svg

web命令產生了很cool的svg圖片，在瀏覽器中開啟。

除了遠程拉取，你還可以自己編寫代碼，把這些資料寫入檔案（實現 net/http/pprof 中的幾個路由，開啟或關閉追蹤資訊）。
具體可參考：http://blog.golang.org/profiling-go-programs
https://github.com/hyper-carrot/go_command_tutorial/blob/master/0.12.md

期間：web命令依賴一個svg產生包，在mac下面，你可以通過http://www.graphviz.org/Download_macos.php進行下載。

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2016.11.14 updated

基於uninx domain socket 的agent，可以不用走http

https://github.com/google/gops