发一个多CPU中进程与CPU绑定的例子

jijo 2009-03-10

展开全文

现在多CPU的趋势越来越大了. 有时候为了更好地操作机器, 需要将某个进程绑定到具体的CPU上去. 下面给出了一个进程绑定到具体的CPU上去的一个例子.

cpu.c

[Copy to clipboard] [ - ]

CODE:

#include<stdlib.h>
#include<stdio.h>
#include<sys/types.h>
#include<sys/sysinfo.h>
#include<unistd.h>

#define __USE_GNU
#include<sched.h>
#include<ctype.h>
#include<string.h>

int main(int argc, char* argv[])
{
      int num = sysconf(_SC_NPROCESSORS_CONF);
      int created_thread = 0;
      int myid;
      int i;
      int j = 0;

      cpu_set_t mask;
      cpu_set_t get;

      if (argc != 2)
      {
            printf("usage : ./cpu num\n");
            exit(1);
      }

      myid = atoi(argv[1]);

      printf("system has %i processor(s). \n", num);

      CPU_ZERO(&mask);
      CPU_SET(myid, &mask);

      if (sched_setaffinity(0, sizeof(mask), &mask) == -1)
      {
            printf("warning: could not set CPU affinity, continuing...\n");
      }
      while (1)
      {

            CPU_ZERO(&get);
            if (sched_getaffinity(0, sizeof(get), &get) == -1)
            {
                     printf("warning: cound not get cpu affinity, continuing...\n");
            }
            for (i = 0; i < num; i++)
            {
                     if (CPU_ISSET(i, &get))
                     {
                              printf("this process %d is running processor : %d\n",getpid(), i);
                     }
            }
      }
      return 0;
}

下面是在两个终端分别执行了./cpu 0 ./cpu 2 后得到的结果. 效果比较明显.

QUOTE:

Cpu0  :  5.3%us,  5.3%sy,  0.0%ni, 87.4%id,  0.0%wa,  0.0%hi,  2.0%si,  0.0%st
Cpu1  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Cpu2  :  5.0%us, 12.2%sy,  0.0%ni, 82.8%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Cpu3  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Cpu4  :  0.0%us,  0.0%sy,  0.0%ni, 99.7%id,  0.3%wa,  0.0%hi,  0.0%si,  0.0%st
Cpu5  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Cpu6  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Cpu7  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st