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Enable shared expert overlap with allgatherv in inference - #4570

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sidsingh-nvidia merged 2 commits into
NVIDIA:mainfrom
sidsingh-nvidia:siddharth/inference-shared-expert-overlap
May 4, 2026
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Enable shared expert overlap with allgatherv in inference#4570
sidsingh-nvidia merged 2 commits into
NVIDIA:mainfrom
sidsingh-nvidia:siddharth/inference-shared-expert-overlap

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What does this PR do ?

Hide the overheads of allgatherv and a bunch of pre-processing in mcore_fused_moe behind shared experts. Only supported for the NvlsAllGathervDispatcher

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sidsingh-nvidia requested review from a team as code owners May 1, 2026 04:16
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svcnvidia-nemo-ci marked this pull request as draft May 1, 2026 04:16
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This PR has been automatically converted to draft because all PRs must start as drafts.

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/claude review

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LGTM

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sidsingh-nvidia marked this pull request as ready for review May 1, 2026 04:32
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svcnvidia-nemo-ci requested a review from a team May 1, 2026 04:32
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/ok to test 7f3bcf4

@ericharper
ericharper enabled auto-merge May 1, 2026 19:53
@svcnvidia-nemo-ci svcnvidia-nemo-ci added the Approved All necessary approvals have been made label May 4, 2026
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sidsingh-nvidia disabled auto-merge May 4, 2026 02:22
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sidsingh-nvidia added this pull request to the merge queue May 4, 2026
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🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/25300459822

Merged via the queue into NVIDIA:main with commit 442a936 May 4, 2026
66 of 71 checks passed
@sidsingh-nvidia
sidsingh-nvidia deleted the siddharth/inference-shared-expert-overlap branch May 4, 2026 04:35
yhgalaxy pushed a commit to yhgalaxy/Megatron-LM that referenced this pull request Jun 17, 2026
mathemakitten pushed a commit to mathemakitten/Megatron-LM that referenced this pull request Jul 1, 2026
jon-barker pushed a commit to jon-barker/Megatron-LM that referenced this pull request Jul 10, 2026
Signed-off-by: Jon Barker <jbarker@aws-cmh-slurm-1-vscode-02.cm.cluster>
terminator123 pushed a commit to 021ai/Megatron-LM that referenced this pull request Aug 3, 2026
svcnvidia-nemo-ci pushed a commit to dimapihtar/Megatron-LM that referenced this pull request Aug 4, 2026
Signed-off-by: Dmytro Pykhtar <dpykhtar@nvidia.com>
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5 participants