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[M-FSDP] Fix Tensor Parallel mode detection#3191

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shjwudp wants to merge 10 commits intoNVIDIA:mainfrom
shjwudp:mfsdp_fix_mcore_tp_detect
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[M-FSDP] Fix Tensor Parallel mode detection#3191
shjwudp wants to merge 10 commits intoNVIDIA:mainfrom
shjwudp:mfsdp_fix_mcore_tp_detect

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@shjwudp shjwudp commented Feb 2, 2026

What does this PR do ?

The TP (Tensor Parallel) mode detection for MCore model parameters in M-FSDP was incorrect in certain cases. This update fixes the issue by aligning the TP mode detection logic (Row, Column, Duplicate) with the Megatron-Bridge implementation.

Based on Megatron-Bridge, fix the detection of TP parallel modes, including Row, Column, and Duplicate.

⚠️ For major changes (either in lines of code or in its impact), please make sure to first share a design doc with the team. If you're unsure what's the best way to do so, contact the @mcore-oncall.

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flowchart LR
    A[Pre-checks] --> B[PR Tests]
    subgraph Code Review/Approval
        C1[Expert Review] --> C2[Final Review]
    end
    B --> C1
    C2 --> D[Merge]
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@shjwudp shjwudp self-assigned this Feb 2, 2026
@shjwudp shjwudp requested review from a team as code owners February 2, 2026 02:47
@shjwudp shjwudp added bug Something isn't working Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. module: megatron-fsdp labels Feb 2, 2026
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copy-pr-bot bot commented Feb 2, 2026

This pull request requires additional validation before any workflows can run on NVIDIA's runners.

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@ko3n1g ko3n1g requested a review from a team February 2, 2026 02:47
@dimapihtar dimapihtar requested a review from BoxiangW February 4, 2026 15:20
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LGTM. Thanky you!

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/ok to test fcd18ff

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shjwudp commented Feb 25, 2026

/ok to test d8b217f

@yaox12 yaox12 added Final Review PR is in the "final review" stage and removed Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. labels Feb 26, 2026
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shjwudp commented Mar 10, 2026

/ok to test 634b15f

@shjwudp shjwudp enabled auto-merge March 10, 2026 09:56
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shjwudp commented Mar 10, 2026

/ok to test 73c19bf

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