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Microsoft Collective Communication Library
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How to set the target buffer size range for MSCCL algorithms #54

Closed rashidi1saeed closed 1 year ago

rashidi1saeed commented 1 year ago

Hi, When I am writing MSCCL All-Reduce algorithms and run nccltest, it seems that for all-reduces greater than 64 MB, the MSCCL runtime falls back to the NCLL algorithm, rather than executing my MSCCL algorithm. How can we determine the buffer size range for our MSCCL algorithms?

Thanks

saeedmaleki commented 1 year ago

Hi Saeed,

For each XML, there are two attributes you can set for the head XML node: minBytes and maxBytes which define the range in which the algorithm would be selected. maxBytes by default, I believe, is 128MB. So, you can overwrite it by setting a larger value.

rashidi1saeed commented 1 year ago

Hi @saeedmaleki , Thanks for the reply! My problem got solved.