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[Sheeep]

Run two queues parallel

Hi,

I tried to use gpu and cpu parallel.

I created two differente queues in two contexts:

queueCPU = cl::CommandQueue(Context, deviceCPU[0]);

queueGPU = cl::CommandQueue(Context, deviceGPU[0]);

I want to execute both queues parallel. 

so I do:

queueCPU.enqueueNDRangeKernel(this->Kernel, cl::NullRange, globalWorkSizeCPU, localWorkSizeCPU, NULL, NULL);

and 

queueGPU.enqueueNDRangeKernel(this->Kernel, cl::NullRange, globalWorkSizeGPU, localWorkSizeGPU, NULL, NULL);

and after enqueueing I want to read the data back to host:

queueCPU.enqueueReadBuffer(this->qBuffer.ioBuffer, true, 0,size, hostpointer);

queueGPU.enqueueReadBuffer(this->qBuffer.ioBuffer, true, 0,size, hostpointer);

If I do it that way, the queues don't run parallel. I think one queue is blocked, so the other can't enqueue, right?

and if I do this (non blocking):

queueCPU.enqueueReadBuffer(this->qBuffer.ioBuffer, false, 0,size, hostpointer);

queueGPU.enqueueReadBuffer(this->qBuffer.ioBuffer, false, 0,size, hostpointer);

they run parallel, but I don't get the right result.

How can I block the memory, and execute the queues parallel?

Sheeep

P.S. sorry for not posting complete code, but is in different classes, so I thinks it's to much. If needed I can make an simple example...

[genaganna]

Take a look at SimpleMultiDevice sample where all combinations explained.

[Sheeep]

Thank you for your answer, 

I'm not familar with the sdk-environment, but if i am right, i have to create some threads with an multithreading framework. like openmp?

I will try to use sdk-environment instead of khronos opencl binding.

EDIT: 

I tried with openmp, works wonderfull (if i don't need any synchronization).

is there a multithreading extension in opencl for the host?