[Bugfix] Fix block size in block_table with PCP #29094
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Signed-off-by: Livinfly <[email protected]>
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This pull request correctly fixes a bug in the block_table by factoring in pcp_world_size for block size calculations, which is essential for correct behavior with Prefill Context Parallelism. The logic change is sound. I have included one review comment suggesting a refactoring to address code duplication for fetching distributed world sizes. This will improve maintainability and prevent potential inconsistencies in the future.
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Yes, we did overlook the logic modifications for MultiGroupBlockTable. Thank you very much for fixing this. |
LucasWilkinson
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Nov 21, 2025
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I discovered a potential issue regarding the missing logic of the block_table in #28718.
In the PCP rank, it should also store only one copy, so the parameter passed from
MultiGroupBlockTabletoBlockTableshould likely be multiplied bycp_world_size. The original code seems to be missing thePCP_world_sizefactor.Could you please verify this, or am I mistaken?
@pisceskkk
Purpose
fix block_table
Test Plan
NA
Test Result
NA
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