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@@ -226,6 +226,21 @@ starpu_resume();
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starpu_shutdown();
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\endcode
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+\section GPUEatingCores When running with CUDA or OpenCL devices, I am seeing less CPU cores
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+
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+Yes, this is on purpose.
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+
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+Since GPU devices are way faster than CPUs, StarPU needs to react quickly when
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+a task is finished, to feed the GPU with another task (StarPU actually submits
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+a couple of tasks in advance so as to pipeline this, but filling the pipeline
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+still has to be happening often enough), and thus it has to dedicate threads for
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+this, and this is a very CPU-consuming duty. StarPU thus dedicates one CPU core
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+for driving each GPU.
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+
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+Such dedication is also useful when a codelet is hybrid, i.e. while kernels are
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+running on the GPU, the codelet can run some computation, which thus be run by
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+the CPU core instead of driving the GPU.
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+
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\section CUDADrivers StarPU does not see my CUDA device
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First make sure that CUDA is properly running outside StarPU: build and
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