Support expert parallel load balancing in Transformers backend #26287
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Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
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This pull request enables expert parallel load balancing (EPLB) for Mixture-of-Experts models using the Transformers backend. This is achieved by implementing the MixtureOfExperts interface in TransformersMoEBase and adding the necessary state and methods for EPLB to function. The changes also include some nice refactoring in transformers.py to consistently use process group objects.
I've found one critical issue in the implementation of update_physical_experts_metadata that would prevent dynamic load balancing from working correctly. Please see my specific comment for details.
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karan
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…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> Signed-off-by: Karan Goel <3261985+karan@users.noreply.github.com>
southfreebird
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…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
xuebwang-amd
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…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> Signed-off-by: xuebwang-amd <xuebwang@amd.com>
lywa1998
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…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
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Oct 24, 2025
…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
xuebwang-amd
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…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com> Signed-off-by: xuebwang-amd <xuebwang@amd.com>
rtourgeman
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…project#26287) Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
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MixtureOfExpertsmixin toTransformersMoEBase