[Core] Fix L40 cublas heuristics - #3440
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Signed-off-by: Jeremy Berchtold <[email protected]>
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Greptile SummaryThe PR constrains cuBLASLt heuristic selection to prevent reduced-precision split-K reductions.
Confidence Score: 5/5The PR appears safe to merge. No blocking failure remains. Important Files Changed
Reviews (2): Last reviewed commit: "[pre-commit.ci] auto fixes from pre-comm..." | Re-trigger Greptile |
ptrendx
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| if (A_type == CUDA_R_16BF && B_type == CUDA_R_16BF && D_type == CUDA_R_16BF && | ||
| gemm_compute_type == CUBLAS_COMPUTE_32F) { |
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Why do we only do this for the BF16 case? I think we should just set this always.
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Good point, I've generalized it to always set this
Signed-off-by: Jeremy Berchtold <[email protected]>
for more information, see https://pre-commit.ci
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Description
In certain cases on L40 we would allow a cuBLASLt heuristic that performed split-K with partial results stored in BF16. This lead to some loss of precision in the results. This PR fixes this by disallowing such heuristics
H100 and above were not observed to be affected by this.
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