v5.0.x: coll/ucc: enable asymmetric datatype check in UCC without OMPI fallback#13657
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QiaoK wants to merge 1 commit intoopen-mpi:v5.0.xfrom
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v5.0.x: coll/ucc: enable asymmetric datatype check in UCC without OMPI fallback#13657QiaoK wants to merge 1 commit intoopen-mpi:v5.0.xfrom
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Is this not a cherry pick of #13656?
If it actually is a cherry-pick -- even if there was some back-porting necessary -- then this PR should not be marked as notacherrypick and the commit message should include the cherry pick message.
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This change enables UCC to perform asymmetric datatype checks internally for gather, gatherv, scatter, and scatterv operations. This feature is only available in UCC 1.8 or greater. The motivation for this change is to avoid scenarios where a subset of processes fallback to OMPI while other processes proceed to UCC when asymmetric datatypes are supplied. By letting UCC handle the datatype asymmetry check, UCC can signal all processes to fallback when necessary, ensuring consistent collective operation execution across all ranks. Signed-off-by: Qiao Kang <qkang@nvidia.com>
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This change enables UCC to perform asymmetric datatype checks internally for gather, gatherv, scatter, and scatterv operations. This feature is only available in UCC 1.8 or greater.
The motivation for this change is to avoid scenarios where a subset of processes fallback to OMPI while other processes proceed to UCC when asymmetric datatypes are supplied. By letting UCC handle the datatype asymmetry check, UCC can signal all processes to fallback when necessary, ensuring consistent collective operation execution across all ranks.