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我是opencl的新手，我遇到了一个奇怪的问题！我有一个还原内核，我重复了几次！问题是，当我分析内核的执行时，经过的时间（排队->结束）几乎相同并且有点增加，但是当我在“C++”代码中测量经过的时间时，执行“clEnqueueNDRangeKernel”行的时间会增加速度很快！！我已经附上了分析的代码和输出！：震惊：

// execute the kernel
globalWorkSize[0] = this->reduction_NumBlocks * this->reduction_NumThreads;
localWorkSize[0] = this->reduction_NumThreads;

//Start Time
ttt.start();

clErrNum = clEnqueueNDRangeKernel(clCommandQueue, kernelReduction, 1, 0,
globalWorkSize, localWorkSize, 0, NULL, &timing_event);
// check if kernel execution generated an error
oclCheckError(clErrNum, CL_SUCCESS);

clFinish(clCommandQueue);
ttt.stop();

//Check Elapsed Time
clGetEventProfilingInfo(timing_event, CL_PROFILING_COMMAND_QUEUED,
sizeof(time_start), &time_start, NULL);
clGetEventProfilingInfo(timing_event, CL_PROFILING_COMMAND_END,
sizeof(time_end), &time_end, NULL);
cout<<"ElapseTime(Execute):"<<(time_end - time_start)/1000<<"us\tTTT:"    <<ttt.getElapsedTimeInMicroSec()<<endl;

这是输出：

    GeForce GTX 550 Ti
    Device Timer Resolution:1000ns
    GpuExecutionTime:160us   C++ElapsedTime:177
    GpuExecutionTime:156us   C++ElapsedTime:167
    GpuExecutionTime:156us   C++ElapsedTime:166
    GpuExecutionTime:189us   C++ElapsedTime:242
    GpuExecutionTime:158us   C++ElapsedTime:215
    ...
    GpuExecutionTime:156us   C++ElapsedTime:253
    GpuExecutionTime:162us   C++ElapsedTime:261
    GpuExecutionTime:157us   C++ElapsedTime:262
    GpuExecutionTime:156us   C++ElapsedTime:254
    GpuExecutionTime:157us   C++ElapsedTime:254
    GpuExecutionTime:160us   C++ElapsedTime:261
    GpuExecutionTime:167us   C++ElapsedTime:279
    GpuExecutionTime:157us   C++ElapsedTime:264
    ...
    GpuExecutionTime:159us   C++ElapsedTime:263
    GpuExecutionTime:157us   C++ElapsedTime:261
    GpuExecutionTime:157us   C++ElapsedTime:260
    GpuExecutionTime:157us   C++ElapsedTime:263
    GpuExecutionTime:264us   C++ElapsedTime:384
    ...
    GpuExecutionTime:156us   C++ElapsedTime:304
    GpuExecutionTime:161us   C++ElapsedTime:314
    GpuExecutionTime:157us   C++ElapsedTime:308
    GpuExecutionTime:160us   C++ElapsedTime:305
    GpuExecutionTime:158us   C++ElapsedTime:311
    GpuExecutionTime:156us   C++ElapsedTime:308
    GpuExecutionTime:157us   C++ElapsedTime:312
    ...
    GpuExecutionTime:157us   C++ElapsedTime:326
    GpuExecutionTime:158us   C++ElapsedTime:326
    GpuExecutionTime:159us   C++ElapsedTime:330
    GpuExecutionTime:158us   C++ElapsedTime:328
    GpuExecutionTime:158us   C++ElapsedTime:335

任何形式的帮助表示赞赏。

PS输入和其他相关变量的大小是固定的！

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