负载平衡.cpp

一个并行计算的代码

// 负载平衡.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include"omp.h"
#include <windows.h>


void smallwork()
{

}

void bigwork()
{
	_int64 sum = 0;
	for(int i = 0; i < 100000000; i++)
		sum += i;
}
int _tmain(int argc, _TCHAR* argv[])
{
	_int64 counter_begin;
	_int64 counter_end;
	_int64 diff1,diff2,diff3;

	QueryPerformanceCounter((LARGE_INTEGER*)&counter_begin);

	for(int i = 0; i < 100; i++)
	{
		if(i < 50)
			smallwork();
		else
			bigwork();
	}
	QueryPerformanceCounter((LARGE_INTEGER*)&counter_end);
	diff1 = counter_end - counter_begin;
	printf("count = %I64d\n",diff1);

	QueryPerformanceCounter((LARGE_INTEGER*)&counter_begin);
#pragma omp parallel for
	for(int i = 0; i < 100; i++)
	{
		if(i < 50)
			smallwork();
		else
			bigwork();
	}
	QueryPerformanceCounter((LARGE_INTEGER*)&counter_end);
	diff2 = counter_end - counter_begin;
	printf("count = %I64d\n",diff2);

	QueryPerformanceCounter((LARGE_INTEGER*)&counter_begin);
#pragma omp parallel for
	for(int i = 0; i < 100; i++)
	{
		if(i % 2)
			smallwork();
		else
			bigwork();
	}
	QueryPerformanceCounter((LARGE_INTEGER*)&counter_end);

	diff3 = counter_end - counter_begin;
	printf("count = %I64d\n",diff3);
	//double r;
	//r = (double)diff1/(double)diff3;
	//printf("Accelerate = %I64d\n",r);
	return 0;
}