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SYCL: Make sure to use a large enough workgroup size for tree traversal #931
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SYCL: Make sure to use a large enough workgroup size for tree traversal #931
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Should nearest be changed too? Should the kernel in MST be changed as well?
Does it affect all kernels?
// FIXME_SYCL | ||
#ifdef KOKKOS_ENABLE_SYCL | ||
if constexpr (std::is_same_v<ExecutionSpace, Kokkos::Experimental::SYCL>) | ||
policy.set_chunk_size(1024); |
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Can you please add a comment on the considerations that went into choosing 1024?
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Not quite sure if there is much behind it rather than that choosing the maximum gave much better performance (than 32 which is what the compiler chose) and I couldn't find a different workgroup size that gave better results (but results don't differ much choosing between 256 and 1024 threads per workgroup).
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Can you please post the results in this issue for different workgroup sizes?
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I'll share it privately.
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Please cc me
Looks like the MST algorithm ( |
Forcing the workgroup size for the tree traversal to 1024 for
SYCL
, improves the tree traversal by 25% in the DBSCAN benchmark.