Thrust sort time measure

gistfile1.txt

/*
 * main.cu
 *
 *  Created on: 2014/11/05
 *      Author: sase
 */


/*
 * tbbTest.cpp
 *
 *  Created on: 2014/11/05
 *      Author: sase
 */

#include <iostream>
#include <math.h>
#include <sys/time.h>
#include <vector>
#include <algorithm>
#include <numeric>
#include <thrust/device_vector.h>
#include <thrust/sort.h>

using std::cout;
using std::endl;
using std::vector;

double gettimeofday_sec(){
	struct timeval t;
	gettimeofday(&t, NULL);
	return (double)t.tv_sec + (double)t.tv_usec * 1e-6;
}

void SortExample(const int n) {
	const int itrmax = 100;
	vector<int> a(n), b(n);
	vector<double> timeSTL, timeTHRUST;
	srand((unsigned) time(NULL));
	for(int itr=0; itr<itrmax; ++itr){
		// Set random array
		for(int i=0; i<n; ++i){
			a[i] = rand()%100;
		}
		std::copy(a.begin(), a.end(), b.begin());

		thrust::device_vector<int> d_a(a.data(), a.data()+n);
		double tstart = gettimeofday_sec();

		// thrust
		thrust::sort(d_a.begin(), d_a.end());

		double tend = gettimeofday_sec();

		// STL
		std::sort(b.begin(), b.end());

		double tendSTL = gettimeofday_sec();

		timeTHRUST.push_back(tend-tstart);
		timeSTL.push_back(tendSTL-tend);
	}
	cout << n << " "
			<< std::accumulate(timeTHRUST.begin(), timeTHRUST.end(), 0.0)/(double)itrmax << " "
			<< std::accumulate(timeSTL.begin(), timeSTL.end(), 0.0)/(double)itrmax << endl;
}

int main(){

//	int size = 100000;
//	SortExample(size);

	for(int size=10000; size<=50000; size+=10000){
		SortExample(size);
	}
	cout << "warmup done" << endl;

	for(int size=10000; size<=500000; size+=10000){
		SortExample(size);
	}
}