linux - gperftools cpu探查器不支持多进程？

根据文档http://gperftools.googlecode.com/svn/trunk/doc/cpuprofile.html，cpu配置文件确实支持多进程，并将生成独立的输出文件:



但是当我尝试如下时:

//main_cmd_argv.cpp

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <gperftools/profiler.h>

int loop(int n) {
    int sum = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            sum = i + j;
            if (sum %3 == 0) {
                sum /= 3;
            }
        }
    }
    return 0;
}

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

    printf("%s\n%s\n", getenv("CPUPROFILE"), getenv("CPUPROFILESIGNAL"));

    if (argc > 1 && strcmp(argv[1], "-s")==0) {
        // single process
        loop(100000);
        printf("stoped\n");
    } else if (argc > 1 && strcmp(argv[1], "-m")==0) {
        // multi process
        pid_t pid = fork();
        if (pid < 0) {
            printf("fork error\n");
            return -1;
        }
        if (pid == 0) {
            loop(100000);
            printf("child stoped\n");
        } else if (pid > 0) {
            loop(10000);
            printf("father stoped\n");
            wait(NULL);
        }
    }

    return 0;
}

//makefile

GPerfTools=/home/adenzhang/tools/gperftools

CCFLAGS=-fno-omit-frame-pointer -g -Wall

ALL_BINS=main_cmd_argv
all:$(ALL_BINS)

main_cmd_argv:main_cmd_argv.o
    g++ $(CCFLAGS) -o $@ $^ -L./ -L$(GPerfTools)/lib -Wl,-Bdynamic -lprofiler -lunwind

.cpp.o:
    g++ $(CCFLAGS) -c -I./ -I$(GPerfTools)/include -fPIC -o $@ $<
clean:
    rm -f $(ALL_BINS) *.o *.prof

//shell命令

$ make
g++ -fno-omit-frame-pointer -g -Wall -c -I./ -I/home/adenzhang/tools/gperftools/include -fPIC -o main_cmd_argv.o main_cmd_argv.cpp
g++ -fno-omit-frame-pointer -g -Wall -o main_cmd_argv main_cmd_argv.o -L./ -L/home/adenzhang/tools/gperftools/lib -Wl,-Bdynamic -lprofiler -lunwind
$ env CPUPROFILE=main_cmd_argv.prof ./main_cmd_argv -s
젩n_cmd_argv.prof
(null)
stoped
PROFILE: interrupts/evictions/bytes = 6686/3564/228416
$ /home/adenzhang/tools/gperftools/bin/pprof --text ./main_cmd_argv ./main_cmd_argv.prof
Using local file ./main_cmd_argv.
Using local file ./main_cmd_argv.prof.
Removing killpg from all stack traces.
Total: 6686 samples
    6686 100.0% 100.0%     6686 100.0% loop
       0   0.0% 100.0%     6686 100.0% __libc_start_main
       0   0.0% 100.0%     6686 100.0% _start
       0   0.0% 100.0%     6686 100.0% main
$ rm main_cmd_argv.prof
$ env CPUPROFILE=main_cmd_argv.prof ./main_cmd_argv -m
젩n_cmd_argv.prof
(null)
father stoped
child stoped
PROFILE: interrupts/evictions/bytes = 0/0/64
PROFILE: interrupts/evictions/bytes = 68/36/2624
$ ls
main_cmd_argv  main_cmd_argv.cpp  main_cmd_argv.o  main_cmd_argv.prof  Makefile
$ /home/adenzhang/tools/gperftools/bin/pprof --text ./main_cmd_argv ./main_cmd_argv.prof
Using local file ./main_cmd_argv.
Using local file ./main_cmd_argv.prof.
$

gperf不支持多进程，有人可以解释吗？谢谢!

最佳答案

很老了，不知道您是否找到答案，但是...

似乎每个线程/分支都应该使用ProfilerRegisterThread()进行注册。
您可以在这两个问题中找到更多信息:Here和Here。

这也是一个示例代码，类似于您的测试用例，其中的fork可以是registered。