Set tensor-parallel attributes irrespective of perform_initialization by ilml · Pull Request #4084 · NVIDIA/Megatron-LM

ilml · 2026-03-31T21:25:17Z

Cherry-pick of a8bad4b441 (ADLR/megatron-lm!4312).

Ensures set_tensor_model_parallel_attributes is called on weights even when perform_initialization=False, so that downstream code relying on tensor_model_parallel, partition_dim, and partition_stride attributes works correctly regardless of the initialization path.

The experts.py changes from the upstream commit were excluded because the local codebase does not contain the GroupedMLP class they target.

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github-actions · 2026-03-31T21:25:26Z

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ilml · 2026-03-31T22:51:35Z

/ok to test dc84bc1

FDecaYed

LGTM. fixing CR header

FDecaYed · 2026-04-03T06:58:17Z

/ok to test 70def0f

Cherry-pick of NVIDIA/Megatron-LM@a8bad4b441 (ADLR/megatron-lm!4312). Ensures `set_tensor_model_parallel_attributes` is called on weights even when `perform_initialization=False`, so that downstream code relying on `tensor_model_parallel`, `partition_dim`, and `partition_stride` attributes works correctly regardless of the initialization path. The experts.py changes from the upstream commit were excluded because the local codebase does not contain the GroupedMLP class they target. Co-authored-by: yaoyu-33 <yaoyu.094@gmail.com> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Signed-off-by: Deyu Fu <deyuf@nvidia.com>

ilml · 2026-04-03T18:59:30Z

/ok to test c8f2838

ilml · 2026-04-03T19:05:49Z

/ok to test 4a57f4e

svcnvidia-nemo-ci · 2026-04-03T19:53:04Z

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/23959990923

…NVIDIA#4084) Signed-off-by: Deyu Fu <deyuf@nvidia.com> Co-authored-by: Tom Long <tolong@oci-hsg-cs-001-vscode-02.cm.cluster> Co-authored-by: yaoyu-33 <yaoyu.094@gmail.com> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Deyu Fu <deyuf@nvidia.com>

…NVIDIA#4084) Signed-off-by: Deyu Fu <deyuf@nvidia.com> Co-authored-by: Tom Long <tolong@oci-hsg-cs-001-vscode-02.cm.cluster> Co-authored-by: yaoyu-33 <yaoyu.094@gmail.com> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Deyu Fu <deyuf@nvidia.com> Signed-off-by: yhgalaxy <yhgalaxy@outlook.com>

…NVIDIA#4084) Signed-off-by: Deyu Fu <deyuf@nvidia.com> Co-authored-by: Tom Long <tolong@oci-hsg-cs-001-vscode-02.cm.cluster> Co-authored-by: yaoyu-33 <yaoyu.094@gmail.com> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Deyu Fu <deyuf@nvidia.com> Signed-off-by: Jon Barker <jbarker@aws-cmh-slurm-1-vscode-02.cm.cluster>

…NVIDIA#4084) Signed-off-by: Deyu Fu <deyuf@nvidia.com> Co-authored-by: Tom Long <tolong@oci-hsg-cs-001-vscode-02.cm.cluster> Co-authored-by: yaoyu-33 <yaoyu.094@gmail.com> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Deyu Fu <deyuf@nvidia.com>

ilml requested review from a team as code owners March 31, 2026 21:25

svcnvidia-nemo-ci marked this pull request as draft March 31, 2026 21:25

ilml marked this pull request as ready for review March 31, 2026 21:27

svcnvidia-nemo-ci requested a review from a team March 31, 2026 21:27

svcnvidia-nemo-ci added the Final Review PR is in the "final review" stage label Mar 31, 2026

ilml force-pushed the cherry-pick-tp-attrs-without-init branch from 6af361e to 1eab659 Compare March 31, 2026 21:28

svcnvidia-nemo-ci added the complexity: low label Mar 31, 2026

jaredcasper approved these changes Mar 31, 2026

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ilml force-pushed the cherry-pick-tp-attrs-without-init branch from 1eab659 to dc84bc1 Compare March 31, 2026 22:48

svcnvidia-nemo-ci added this to the Core 0.16 milestone Mar 31, 2026

copy-pr-bot Bot temporarily deployed to test March 31, 2026 22:52 Inactive

FDecaYed approved these changes Apr 3, 2026

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FDecaYed enabled auto-merge April 3, 2026 06:53

copy-pr-bot Bot temporarily deployed to test April 3, 2026 06:59 Inactive

FDecaYed removed the request for review from a team April 3, 2026 07:00

ilml force-pushed the cherry-pick-tp-attrs-without-init branch from 70def0f to 9fa50eb Compare April 3, 2026 17:40

ericharper approved these changes Apr 3, 2026

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svcnvidia-nemo-ci added Approved All necessary approvals have been made and removed Final Review PR is in the "final review" stage labels Apr 3, 2026

Tom Long and others added 2 commits April 3, 2026 11:57

fix copyright

c8f2838

Signed-off-by: Deyu Fu <deyuf@nvidia.com>

ilml force-pushed the cherry-pick-tp-attrs-without-init branch from 9fa50eb to c8f2838 Compare April 3, 2026 18:57

Merge branch 'main' into cherry-pick-tp-attrs-without-init

4a57f4e

copy-pr-bot Bot temporarily deployed to test April 3, 2026 19:06 Inactive

FDecaYed added this pull request to the merge queue Apr 3, 2026

Merged via the queue into NVIDIA:main with commit a72c027 Apr 3, 2026
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Set tensor-parallel attributes irrespective of perform_initialization - #4084

Set tensor-parallel attributes irrespective of perform_initialization#4084
FDecaYed merged 3 commits into
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ilml:cherry-pick-tp-attrs-without-init

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ilml commented Mar 31, 2026

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