google-perftools的用法

假设你已经安装好了这个开源工具

1） vim example.cpp

#include<iostream>

#include<stdlib.h>

//#include<google/profiler.h>

#include<stdio.h>

using namespace std;

void consumeSomeCPUTime1(int input){ 

        int i = 0; 

        input++; 

        while(i++ < 10000){ 

                i--;  i++;  i--;  i++; 

        } 

}; 

void consumeSomeCPUTime2(int input){ 

        input++; 

        consumeSomeCPUTime1(input); 

        int i = 0; 

        while(i++ < 10000){ 

                i--;  i++;  i--;  i++; 

        } 

}; 

int stupidComputing(int a, int b){ 

        int i = 0; 

        while( i++ < 10000){  

                consumeSomeCPUTime1(i); 

        } 

        int j = 0; 

        while(j++ < 5000){ 

                consumeSomeCPUTime2(j); 

        } 

        return a+b; 

}; 

int smartComputing(int a, int b){ 

        return a+b; 

}; 

int main(){ 

        int i = 0;

        printf("reached the start point of performance bottle neck\n"); 

        sleep(1);

//      ProfilerStart("CPUProfile.prof");

        while( i++ < 10){ 

                printf("Stupid computing return : %d\n",stupidComputing(i, i+1)); 

                printf("Smart computing return %d\n",smartComputing(i+1, i+2)); 

        }

        printf("should teminate profiling now.\n");  

        sleep(1);

//      ProfilerStop();

        return 0;

} 

2）设置 LD_LIBRARY_PATH就是你的pprof的安装路径下的lib

3）设置ＣＰＵＰＲＯＦＩＬＥ的值如：ＣＰＵＰＲＯＦＩＬＥ＝ｃｐｕ；

这里还可以再源文件里面加入被注释掉的语句来设置ｃｐｕｐｒｏｆｉｌｅ输出的结果

如果是多线程的话就需要使用ＰｒｏｆｉｌｅｒＲｅｇｉｓｔｅｒＴｈｒｅａｄ（）；这样在每个线程执行的时候就注册了一次

４）编译g++ -g ｅｘａｍｐｌｅ.cpp -L/usr/local/lib/   -lprofiler -o ｅｘａｍｐｌｅ

５）执行ｅｘａｍｐｌｅ就会生成ｃｐｕ文件

６）查看结果　　pprof －-text profile ｃｐｕ＞＞ｔ１．ｔｘｔ　　这里是以ｔｅｘｔ的格式查看函数调用关系　和耗时；也可以用－－ｄｏｔ的格式查看；然后再将其转换成ｇｉｆ格式就可以看调用关系图：pprof -－ｄｏｔ　profile ｃｐｕ＞ｔ１．ｄｏｔ

７）将ｄｏｔ文件下载到本地然后用Graphviz软件转换为ｇｉｆ格式就可以查看函数调用关系了

ｐｓ：统计的结果

 

 

 

/* This demo case is write by yulong.yhj@taobao.com

* If you have any question, please don't hesitate to contact me.

* You also can contact me with ÍúÍú: ÓñÁú

* Compile the Demo:

I find if we modify the code and call ProfilerRegisterThread(); for each thread. It can capture profiling samples for each thread.

LD_LIBRARY_PATH=/home/admin/google-perftools/lib g++ testvar.cpp -o testvar -lpthread -lprofiler -L/home/admin/google-perftools/lib -I/home/admin/google-perftools/include

* "/home/admin/google-perftools/lib" is the install folder of google perftools and  libunwind libary.

* Run the demo with google CPU Profile

LD_LIBRARY_PATH=/home/admin/google-perftools/lib ./testvar  

*

*

*

*/

#include <stdio.h>

#include <signal.h>

#include <unistd.h>

#include <iostream.h>

#include <pthread.h>

#include<sys/types.h>

#include <time.h>

#include <sys/time.h>

#include <google/profiler.h>

int gvar = 1000;

static void sig_hook(int sig) {

        if( sig == SIGINT || sig == SIGTERM ) {

                cout<<"---------------STOPPING----------------"<<endl;

                //kill(getpid(), SIGKILL);

        exit(1);

        }

}

void calcA(){

 long i=1;

        while(i<1000000){

    int a =333;

    int b=777;

    int c =0;

    c =a * b;

    i++;

    }

}

void calcB(){

 static int a =0;

 long i=1;

    while(i<1000000){

    int a =333;

    int b=777;

    int c =0;

    c =a * b;

    i++;

    }

  if(a==100)sleep(3);

  a++;

}

void calcC(){

  //static int a = 0;

 long i=1;

    while(i<1000000){

    int a =333;

    int b=777;

    int c =0;

    c =a * b;

    i++;

    }

    //if(a==100)sleep(3);

    //a++;

}

void calcA2(){

  //static int a = 0;

 long i=1;

    while(i<1000000){

    int a =333;

    int b=777;

    int c =0;

    c =a * b;

    i++;

    }

    //if(a==100)sleep(3);

    //a++;

}

void * threadA(void *){

ProfilerRegisterThread();

while(true){

calcA();

}

}

void * threadA2(void *){

ProfilerRegisterThread();

while(true){

calcA2();

}

}

void * threadB(void *){

ProfilerRegisterThread();

while(true){

calcB();

}

}

int main(int argc, char * argv[]) {

     ProfilerStart("gvar.prof") ;

  int enable=  ProfilingIsEnabledForAllThreads();

   cout<<"Profiling Enabled:"<<enable<<endl;

   cout<<"GVar value: "<< gvar<<endl;

    long start = time(0);

    struct timeval tvstart;

    struct timeval tvend;

    gettimeofday(&tvstart, NULL);

        signal(SIGINT, sig_hook);

        signal(SIGTERM, sig_hook);

     pthread_t id1;

     pthread_t id2;

     pthread_t id3;

     pthread_create(&id1,NULL, threadA,NULL);

     pthread_create(&id2,NULL, threadB,NULL);

     pthread_create(&id3,NULL, threadA2, NULL);

     long i=0;

     while(i<2000){

     calcC();

     i++;

    }

    long end = time(0);

    gettimeofday(&tvend, NULL);

    long rt = (tvend.tv_usec - tvstart.tv_usec)/1000+(tvend.tv_sec-tvstart.tv_sec)*1000;

    cout<<"Total Time: "<<rt<<" ms"<<endl;

    cout<<"Finished Main Thread"<<endl;

     ProfilerStop();

}