ceph/src/boost/libs/compute/perf/perf_thrust_saxpy.cu

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2013-2014 Kyle Lutz <kyle.r.lutz@gmail.com>
   3 //
   4 // Distributed under the Boost Software License, Version 1.0
   5 // See accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt
   7 //
   8 // See http://boostorg.github.com/compute for more information.
   9 //---------------------------------------------------------------------------//
  10
  11 #include <iostream>
  12 #include <iterator>
  13 #include <algorithm>
  14
  15 #include <thrust/device_vector.h>
  16 #include <thrust/functional.h>
  17 #include <thrust/host_vector.h>
  18 #include <thrust/transform.h>
  19
  20 #include "perf.hpp"
  21
  22 struct saxpy_functor : public thrust::binary_function<float,float,float>
  23 {
  24     const float a;
  25
  26     saxpy_functor(float _a) : a(_a) {}
  27
  28     __host__ __device__
  29     float operator()(const float& x, const float& y) const
  30     {
  31         return a * x + y;
  32     }
  33 };
  34
  35 int main(int argc, char *argv[])
  36 {
  37     perf_parse_args(argc, argv);
  38
  39     std::cout << "size: " << PERF_N << std::endl;
  40     thrust::host_vector<int> host_x(PERF_N);
  41     thrust::host_vector<int> host_y(PERF_N);
  42     std::generate(host_x.begin(), host_x.end(), rand);
  43     std::generate(host_y.begin(), host_y.end(), rand);
  44
  45     // transfer data to the device
  46     thrust::device_vector<int> device_x = host_x;
  47     thrust::device_vector<int> device_y = host_y;
  48
  49     perf_timer t;
  50     for(size_t trial = 0; trial < PERF_TRIALS; trial++){
  51         t.start();
  52         thrust::transform(device_x.begin(), device_x.end(), device_y.begin(), device_y.begin(), saxpy_functor(2.5f));
  53         cudaDeviceSynchronize();
  54         t.stop();
  55     }
  56     std::cout << "time: " << t.min_time() / 1e6 << " ms" << std::endl;
  57
  58     // transfer data back to host
  59     thrust::copy(device_x.begin(), device_x.end(), host_x.begin());
  60     thrust::copy(device_y.begin(), device_y.end(), host_y.begin());
  61
  62     return 0;
  63 }