Go: pprof与性能分析

pprof是非常好用的性能分析工具

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$非服务类程序$

源代码：

package main import ( "fmt" "time" ) func dfs(ans *[][]int,path []int,sum int,k int){ if sum > k { return } if sum == k { *ans = append(*ans, path) return } for i:=1;i<10;i++{ t := i path = append(path, t) sum += t dfs(ans, path, sum, k) sum -= t path = path[:len(path)-1:len(path)-1] } } func solve(k int) [][]int{ ans := make([][]int,0) path := make([]int,0) dfs(&ans,path,0,k) return ans } func main(){ start := time.Now() fmt.Println(len(solve(24))) fmt.Println(time.Since(start)) }

$cpu性能分析：$

package main import ( "flag" "fmt" "log" "os" "runtime/pprof" "time" ) var cpuProfile = flag.String("cpuprofile","","write cpu profile to file") func dfs(ans *[][]int,path []int,sum int,k int){ if sum > k { return } if sum == k { *ans = append(*ans, path) return } for i:=1;i<10;i++{ t := i path = append(path, t) sum += t dfs(ans, path, sum, k) sum -= t path = path[:len(path)-1:len(path)-1] } } func solve(k int) [][]int{ ans := make([][]int,0) path := make([]int,0) dfs(&ans,path,0,k) return ans } func main(){ flag.Parse() if *cpuProfile != "" { f, err := os.Create(*cpuProfile) if err != nil { log.Fatal(err) } _ = pprof.StartCPUProfile(f) defer pprof.StopCPUProfile() } start := time.Now() fmt.Println(len(solve(24))) fmt.Println(time.Since(start)) }

程序运行完毕后：

go tool pprof algorithm cpuProfile.prof top10 # 前10个 top5 -cum # 按cum排序 web # 输出图文件 web growslice # 查看特定函数的图文件

$mem性能分析：$

package main import ( "flag" "fmt" "log" "os" "runtime/pprof" "time" ) var cpuProfile = flag.String("cpuprofile","","write cpu profile to file") var memprofile = flag.String("memprofile","","write memory profile to this file") func dfs(ans *[][]int,path []int,sum int,k int){ if sum > k { return } if sum == k { *ans = append(*ans, path) return } for i:=1;i<10;i++{ t := i path = append(path, t) sum += t dfs(ans, path, sum, k) sum -= t path = path[:len(path)-1:len(path)-1] } } func solve(k int) [][]int{ ans := make([][]int,0) path := make([]int,0) dfs(&ans,path,0,k) return ans } func main(){ flag.Parse() if *cpuProfile != "" { f, err := os.Create(*cpuProfile) if err != nil { log.Fatal(err) } _ = pprof.StartCPUProfile(f) defer pprof.StopCPUProfile() } start := time.Now() fmt.Println(len(solve(24))) fmt.Println(time.Since(start)) if *memprofile != "" { f, err := os.Create(*memprofile) if err != nil { log.Fatal(err) } _ = pprof.WriteHeapProfile(f) defer pprof.StopCPUProfile() } }

程序运行完毕后：

go tool pprof algorithm memProfile.mprof top5 # 列出top5 list main.dfs # 列出函数dfs

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$对于服务类型，需要在main文件中加入：$

import _ "net/http/pprof" func main(){ go func(){ http.ListenAndServe("0.0.0.0:8899",nil) }() }

在服务运行后，来分析数据：

go tool pprof -inuse_space http://your_ip:8899/debug/pprof/heap

进入命令交互洁面，top查看占用比：

top

图片分析更直观：

go tool pprof -inuse_space -cum -svg http://your_ip:8899/debug/pprof/heap > heap_inuse.svg

参考： Profiling Go Programs + 优秀中文翻译 【实践】使用Go pprof做内存性能分析 Go pprof性能调优 Golang 大杀器之性能剖析 PProf