多核多執行緒——pthread_setaffinity_np,cpulimit分析CPU資源對應用程式的影響
阿新 • • 發佈：2019-01-28
#define _GNU_SOURCE
#include <stdio.h>
#include <math.h>
#include <pthread.h>
cpu_set_t cpuset,cpuget;
double waste_time(long n)
{
double res = 0;
long i = 0;
while (i <n * 200000000) {
i++;
res += sqrt(i);
}
return res;
}
void *thread_func(void *param)
{
CPU_ZERO(&cpuset);
CPU_SET(0, &cpuset); /* cpu 0 is in cpuset now */
/* bind process to processor 0 */
if (pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset) !=0) {
perror("pthread_setaffinity_np");
}
printf("Core 0 is running!\n");
/* waste some time so the work is visible with "top" */
printf("result: %f\n", waste_time(5));
pthread_exit(NULL);
}
int main(int argc, char *argv[])
{
pthread_t my_thread;
time_t startwtime, endwtime;
startwtime = time (NULL);
if (pthread_create(&my_thread, NULL, thread_func,NULL) != 0) {
perror("pthread_create");
}
pthread_join(my_thread,NULL);
endwtime = time (NULL);
printf ("wall clock time = %d\n", (endwtime - startwtime));
return 0;
}
這段
#include <stdio.h>
#include <math.h>
#include <pthread.h>
cpu_set_t cpuset,cpuget;
double waste_time(long n)
{
double res = 0;
long i = 0;
while (i <n * 200000000) {
i++;
res += sqrt(i);
}
return res;
}
void *thread_func(void *param)
{
CPU_ZERO(&cpuset);
CPU_SET(0, &cpuset); /* cpu 0 is in cpuset now */
/* bind process to processor 0 */
if (pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset) !=0) {
perror("pthread_setaffinity_np");
}
printf("Core 0 is running!\n");
/* waste some time so the work is visible with "top" */
printf("result: %f\n", waste_time(5));
pthread_exit(NULL);
}
int main(int argc, char *argv[])
{
pthread_t my_thread;
time_t startwtime, endwtime;
startwtime = time (NULL);
if (pthread_create(&my_thread, NULL, thread_func,NULL) != 0) {
perror("pthread_create");
}
pthread_join(my_thread,NULL);
endwtime = time (NULL);
printf ("wall clock time = %d\n", (endwtime - startwtime));
return 0;
}
這段