CUDA学习入门2

#include
#include
#include
#include
#include
#include
#include ///cpu
#include
#include template <class T>
void cpu_sort(T begin, T end)
{std::sort(begin, end);
}void gpu_sort(thrust::host_vector<int> &h_vec)
{// transfer data to the devicethrust::device_vector<int> d_vec &＃61; h_vec;// sort data on the device (846M keys per second on GeForce GTX 480)
thrust::sort(d_vec.begin(), d_vec.end());// transfer data back to host
thrust::copy(d_vec.begin(), d_vec.end(), h_vec.begin());
}#define CHK_TIME(x) {int t1&＃61;GetTickCount();x;int t2&＃61;GetTickCount();printf(#x ": %d\n", t2-t1);}int main(void)
{// generate 32M random numbers seriallythrust::host_vector<int> h_vec(32 <<20);std::generate(h_vec.begin(), h_vec.end(), rand);thrust::host_vector<int> h_vec_1(h_vec);CHK_TIME(cpu_sort(h_vec_1.begin(), h_vec_1.end()));thrust::host_vector<int> h_vec_2(h_vec);CHK_TIME(gpu_sort(h_vec_2));return 0;
}

&＃xff08;debug version&＃xff09;
cpu_sort(h_vec_1.begin(), h_vec_1.end()): 94609
gpu_sort(h_vec_2): 3312
&＃xff08;release version&＃xff09;
cpu_sort(h_vec_1.begin(), h_vec_1.end()): 2828
gpu_sort(h_vec_2): 594

http://stackoverflow.com/questions/6502151/parallel-sorting-on-cuda
Many GPU sorting implementations are variants of the bitonic sort, which is pretty well known and described in most reasonable texts on algorithms published in the last 25 or 30 years.The "reference" sorting implementation for CUDA done by Nadathur Satish from Berkeley and Mark Harris and Michael Garland from NVIDIA (paper here) is a radix sort, and forms the basis of what is in NPP and Thrust.

Eliminates unnecessary copying of data to/from CPU memoryProcess data that is already in GPU memoryLeave results in GPU memory so they are ready for subsequent processingData Exchange and InitializationSet, Convert, Copy, CopyConstBorder, Transpose, SwapChannelsArithmetic and Logical OperationsAdd, Sub, Mul, Div, AbsDiff, Threshold, CompareColor ConversionRGBToYCbCr, YcbCrToRGB, YCbCrToYCbCr, ColorTwist, LUT_LinearFilter FunctionsFilterBox, Filter, FilterRow, FilterColumn, FilterMax, FilterMin, Dilate, Erode, SumWindowColumn, SumWindowRowJPEGDCTQuantInv, DCTQuantFwd, QuantizationTableJPEGGeometry TransformsMirror, WarpAffine, WarpAffineBack, WarpAffineQuad, WarpPerspective, WarpPerspectiveBack , WarpPerspectiveQuad, ResizeStatistics FunctionsMean_StdDev, NormDiff, Sum, MinMax, HistogramEven, RectStdDev