查看linux线程的CPU占用率

测试代码如下：

#include <sys/prctl.h>
#include <pthread.h>

void *thread_routine(void *arg)
{
prctl(PR_SET_NAME, "child_thread");
int i = 0;
while(1)
{
i++;
i = i * 12345;
}
return (void *)0;
}

int main( void )
{
pthread_t handle;
pthread_create(&handle, NULL, thread_routine, NULL);
pthread_join(handle, NULL);
return 0;
}

编译成可执行文件  test.
然后，执行 test.

下面是分析这个进程里面的线程的CPU占用率.

方法1：

$ ps -C test -L -o pid,tid,psr,pcpu,comm
PID TID PSR %CPU COMMAND
22849 22849 3 0.0 test
22849 22850 1 99.9 child_thread方法2:
以 top -H 执行，然后，按 f键， 按空格键 选中

P       = Last Used Cpu (SMP)

，按Esc后者 q退出，输出结果如下：

Threads: 742 total, 3 running, 738 sleeping, 0 stopped, 1 zombie
%Cpu(s): 40.6 us, 2.5 sy, 0.1 ni, 56.5 id, 0.2 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 4086928 total, 670704 free, 1989828 used, 1426396 buff/cache
KiB Swap: 4140028 total, 3609488 free, 530540 used. 1507048 avail Mem

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND P
22850 charles 20 0 10512 592 532 R 99.9 0.0 22:01.90 child_thread 3
28277 charles 20 0 1601204 457328 138820 R 36.8 11.2 214:36.88 Compositor 1
1191 root 20 0 347380 106852 67784 S 11.1 2.6 955:34.67 Xorg 0
2069 charles 20 0 422700 120328 37048 S 9.4 2.9 595:07.34 compiz 0

或者：
$ pidof test
22849
$ top -H -p 22849
KiB Mem : 4086928 total, 335404 free, 2245788 used, 1505736 buff/cache
KiB Swap: 4140028 total, 3613268 free, 526760 used. 1263944 avail Mem

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
22850 charles 20 0 10512 592 532 R 99.9 0.0 118:54.15 child_thread
22849 charles 20 0 10512 592 532 S 0.0 0.0 0:00.00 test