多核CPU利用测试

#include "stdafx.h"
#include <iostream>
#include <cmath>
#include <ctime>
#include <windows.h>

using namespace std;

//得到循环0xFFFFFFFF次用的秒数
unsigned int test()
{
    unsigned int c = 0xFFFFFFFF;

    time_t t1, t2;
    time(&t1);

    for(unsigned int i = 0; i < c; i++)
        ;
    time(&t2);
    return (unsigned int)(t2 -t1);

}


#define T  20000                                        //周期时间 20秒
#define C  100                                            //采样点时间间隔
#define PI 3.1415                                        //PI
const unsigned int count = 0xFFFFFFFF / (test() *1000); //采样间隔可以执行的循环数目
const unsigned int N = T/C;                                //周期内采样点数目
unsigned int v[N] = { 0 };                                //所有采样点连续执行循环数
unsigned int mt[N] = { 0 };                                //所有采样点休眠毫秒数

int main()
{
    //指定运行CPU
    SetThreadAffinityMask(GetCurrentThread(), 3);
　　
    for(int i = 0; i < N; i++)
    {
        double x = 2 * PI * i / N;
        double r = (sin(x) + 1) / 2;

        mt[i] = C - r * C;
        v[i] = r * C * count;
    }
    for(;;)
    {
        for(int i = 0; i < N; i++)
        {
            for(int j = 0; j < v[i]; j++)
                ;
            Sleep(mt[i]);
        }
    }
}