现在的CPU几乎都是多核，所以，分配给予进程相同数量的线程是合理的需求
但是，这些线程不一定就均匀跑在这些内核上
所以，我们要指派，“一个线程就运行在一个固定的CPU内核上”
//test.c
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
#include <sched.h>
void *myfun(void *arg)
{
cpu_set_t mask;
cpu_set_t get;
char buf[256];
int i;
int j;
int num = sysconf(_SC_NPROCESSORS_CONF);
printf("system has %d processor(s) ", num);
for (i = 0; i < num; i++) {
CPU_ZERO(&mask);
CPU_SET(i, &mask);
if (pthread_setaffinity_np(pthread_self(), sizeof(mask), &mask) < 0) {
fprintf(stderr, "set thread affinity failed ");
}
CPU_ZERO(&get);
if (pthread_getaffinity_np(pthread_self(), sizeof(get), &get) < 0) {
fprintf(stderr, "get thread affinity failed ");
}
for (j = 0; j < num; j++) {
if (CPU_ISSET(j, &get)) {
printf("thread %d is running in processor %d ", (int)pthread_self(), j);
}
}
j = 0;
while (j++ < 100000000) {
memset(buf, 0, sizeof(buf));
}
}
pthread_exit(NULL);
}
int main(int argc, char *argv[])
{
pthread_t tid;
if (pthread_create(&tid, NULL, (void *)myfun, NULL) != 0) {
fprintf(stderr, "thread create failed ");
return -1;
}
pthread_join(tid, NULL);
return 0;
}
//result
#gcc -o test.o -c test.c
#gcc -o test test.o -lpthread
#./test
Finally:
这项技术特别有用，不多说了