fix(megatron-fsdp): build expt_device_mesh only for MoE models by xuwchen · Pull Request #3831 · NVIDIA/Megatron-LM

xuwchen · 2026-03-12T13:23:34Z

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xuwchen · 2026-03-13T06:06:39Z

/ok to test adec596

Phlip79 · 2026-04-13T16:40:00Z

/ok to test 334532d

svcnvidia-nemo-ci · 2026-04-13T18:42:04Z

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/24360572380

svcnvidia-nemo-ci · 2026-04-13T18:42:42Z

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/24360600900

…A#3831)

…A#3831) Signed-off-by: yhgalaxy <yhgalaxy@outlook.com>

…A#3831) Signed-off-by: Jon Barker <jbarker@aws-cmh-slurm-1-vscode-02.cm.cluster>

# Description NVIDIA#4024 NVIDIA#3746 NVIDIA#2799 NVIDIA#3676 NVIDIA#4133 NVIDIA#3295 NVIDIA#3831 NVIDIA#3754 ## Type of change - [ ] New feature (non-breaking change which adds functionality) - [ ] Infra/Build change (changes to CI/CD workflows or build scripts) - [ ] Code refactoring - [ ] Documentation change - [x] Bug fix - [ ] Breaking change ## Changes - Content 1 - Content 2 - Content 3 - Content 4 ## Checklist - [ ] I have read and followed the contributing guidelines - [ ] The functionality is complete - [ ] I have commented my code, particularly in coverage report uploading steps - [ ] I have made corresponding changes to the documentation - [ ] My changes generate no new warnings - [ ] I have added/updated tests that prove my feature works - [ ] New and existing unit tests pass locally --------- Signed-off-by: Cory Ye <cye@nvidia.com> Signed-off-by: yexiaochuan <yexiaochuan@baidu.com> Signed-off-by: Akshat Kumar <akshat230405@gmail.com> Signed-off-by: Youngeun Kwon <youngeunk@nvidia.com> Signed-off-by: jinliangl <jinliangl@nvidia.com> Co-authored-by: Ritesh Patel <ripatel@nvidia.com> Co-authored-by: Cory Ye <cye@nvidia.com> Co-authored-by: Cory Ye <44509866+cspades@users.noreply.github.com> Co-authored-by: Xiaochuan Ye <tap91624@gmail.com> Co-authored-by: yexiaochuan <yexiaochuan@baidu.com> Co-authored-by: Akshat8510 <akshat230405@gmail.com> Co-authored-by: Kunlun Li <94586211+kunlunl@users.noreply.github.com> Co-authored-by: eternally-z <zzywzj@gmail.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com> Co-authored-by: Youngeun Kwon <youngeunk@nvidia.com> Co-authored-by: xuwchen <xuwenc@nvidia.com> Co-authored-by: Li Jinliang <jinliangl@nvidia.com>

…A#3831)

xuwchen added 2 commits March 12, 2026 06:17

build expt_device_mesh only for MoE models

12012f1

add unit test for expt_device_mesh for dense and moe models

aa4085b

xuwchen requested review from a team as code owners March 12, 2026 13:23

svcnvidia-nemo-ci marked this pull request as draft March 12, 2026 13:23

xuwchen mentioned this pull request Mar 12, 2026

[DEV] fix(megatron-fsdp): build expt_device_mesh only for MoE models #3832

Merged

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shjwudp assigned xuwchen Mar 13, 2026

shjwudp added module: megatron-fsdp Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. labels Mar 13, 2026

format

adec596

svcnvidia-nemo-ci added this to the Core 0.16 milestone Mar 13, 2026

copy-pr-bot Bot temporarily deployed to test March 13, 2026 06:07 Inactive

shjwudp approved these changes Mar 13, 2026

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Phlip79 marked this pull request as ready for review March 24, 2026 17:42

svcnvidia-nemo-ci added the Final Review PR is in the "final review" stage label Mar 24, 2026

svcnvidia-nemo-ci requested a review from a team March 24, 2026 17:42

svcnvidia-nemo-ci added the complexity: low label Mar 24, 2026

Phlip79 marked this pull request as draft March 24, 2026 17:55

Merge branch 'main' into fix_expt_device_mesh

334532d

xuwchen marked this pull request as ready for review April 5, 2026 07:26

svcnvidia-nemo-ci added complexity: low and removed complexity: low labels Apr 5, 2026

xuwchen enabled auto-merge April 5, 2026 07:37

Phlip79 removed the Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. label Apr 6, 2026

jaredcasper approved these changes Apr 9, 2026

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ericharper approved these changes Apr 12, 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 12, 2026

copy-pr-bot Bot temporarily deployed to test April 13, 2026 16:41 Inactive

xuwchen added this pull request to the merge queue Apr 13, 2026

Merged via the queue into NVIDIA:main with commit 25129bf Apr 13, 2026
67 of 68 checks passed

xuwchen deleted the fix_expt_device_mesh branch April 13, 2026 20:05

svcnvidia-nemo-ci mentioned this pull request Apr 14, 2026

chore: nightly sync main into dev (14_04_2026) #4291

Merged

yangbofun pushed a commit to xlm-research/Megatron-LM that referenced this pull request May 22, 2026

fix(megatron-fsdp): build expt_device_mesh only for MoE models (NVIDI…

247d8c4

…A#3831)

yhgalaxy pushed a commit to yhgalaxy/Megatron-LM that referenced this pull request Jun 17, 2026

fix(megatron-fsdp): build expt_device_mesh only for MoE models (NVIDI…

aec3a78

…A#3831) Signed-off-by: yhgalaxy <yhgalaxy@outlook.com>

jon-barker pushed a commit to jon-barker/Megatron-LM that referenced this pull request Jul 10, 2026

fix(megatron-fsdp): build expt_device_mesh only for MoE models (NVIDI…

931dfbb

…A#3831) Signed-off-by: Jon Barker <jbarker@aws-cmh-slurm-1-vscode-02.cm.cluster>

zhaoyinglia mentioned this pull request Jul 16, 2026

cherry-pick fix pr for megatron_fsdp flagos-ai/Megatron-LM-FL#79

Merged

13 tasks

terminator123 pushed a commit to 021ai/Megatron-LM that referenced this pull request Aug 3, 2026

fix(megatron-fsdp): build expt_device_mesh only for MoE models (NVIDI…

276ebd8

…A#3831)

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fix(megatron-fsdp): build expt_device_mesh only for MoE models - #3831

fix(megatron-fsdp): build expt_device_mesh only for MoE models#3831
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xuwchen commented Mar 12, 2026

What does this PR do ?

Contribution process

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