ceph/src/boost/libs/compute/example/time_copy.cpp

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2013 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 //[time_copy_example
  12
  13 #include <vector>
  14 #include <cstdlib>
  15 #include <iostream>
  16
  17 #include <boost/compute/event.hpp>
  18 #include <boost/compute/system.hpp>
  19 #include <boost/compute/algorithm/copy.hpp>
  20 #include <boost/compute/async/future.hpp>
  21 #include <boost/compute/container/vector.hpp>
  22
  23 namespace compute = boost::compute;
  24
  25 int main()
  26 {
  27     // get the default device
  28     compute::device gpu = compute::system::default_device();
  29
  30     // create context for default device
  31     compute::context context(gpu);
  32
  33     // create command queue with profiling enabled
  34     compute::command_queue queue(
  35         context, gpu, compute::command_queue::enable_profiling
  36     );
  37
  38     // generate random data on the host
  39     std::vector<int> host_vector(16000000);
  40     std::generate(host_vector.begin(), host_vector.end(), rand);
  41
  42     // create a vector on the device
  43     compute::vector<int> device_vector(host_vector.size(), context);
  44
  45     // copy data from the host to the device
  46     compute::future<void> future = compute::copy_async(
  47         host_vector.begin(), host_vector.end(), device_vector.begin(), queue
  48     );
  49
  50     // wait for copy to finish
  51     future.wait();
  52
  53     // get elapsed time from event profiling information
  54     boost::chrono::milliseconds duration =
  55         future.get_event().duration<boost::chrono::milliseconds>();
  56
  57     // print elapsed time in milliseconds
  58     std::cout << "time: " << duration.count() << " ms" << std::endl;
  59
  60     return 0;
  61 }
  62
  63 //]