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Add missing knob for reduce_scatter_with_fp32_accumulation - #4410

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asolergi-nv merged 5 commits into
NVIDIA:mainfrom
WanZzzzzz:fp4_param_small_fix
Apr 25, 2026
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Add missing knob for reduce_scatter_with_fp32_accumulation#4410
asolergi-nv merged 5 commits into
NVIDIA:mainfrom
WanZzzzzz:fp4_param_small_fix

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@WanZzzzzz

@WanZzzzzz WanZzzzzz commented Apr 21, 2026

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What does this PR do ?

Since only 1 bucket per bucket group is supported with reduce_scatter_with_fp32_accumulation=True, current parition_bucket() is able to handle this case when reduce_scatter_with_fp32_accumulation=True and fp8/fp4_param_gather is True. However, the knob reduce_scatter_with_fp32_accumulation is missing when partition_bucket() is called. This PR fixes this issue.

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Signed-off-by: qiyuw <qiyuw@nvidia.com>
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WanZzzzzz requested review from a team as code owners April 21, 2026 19:19
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svcnvidia-nemo-ci marked this pull request as draft April 21, 2026 19:19
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This PR has been automatically converted to draft because all PRs must start as drafts.

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@WanZzzzzz
WanZzzzzz marked this pull request as ready for review April 21, 2026 19:19
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svcnvidia-nemo-ci requested a review from a team April 21, 2026 19:19
@svcnvidia-nemo-ci svcnvidia-nemo-ci added Final Review PR is in the "final review" stage complexity: low labels Apr 21, 2026
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deepakn94 enabled auto-merge April 23, 2026 21:09
@svcnvidia-nemo-ci svcnvidia-nemo-ci added Approved All necessary approvals have been made and removed Final Review PR is in the "final review" stage labels Apr 23, 2026
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/ok to test 3e40da3

@svcnvidia-nemo-ci svcnvidia-nemo-ci added this to the Core 0.16 milestone Apr 23, 2026
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deepakn94 added this pull request to the merge queue Apr 23, 2026
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🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/24863073339

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/ok to test 5e736e7

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asolergi-nv enabled auto-merge April 25, 2026 20:07
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asolergi-nv added this pull request to the merge queue Apr 25, 2026
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🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/24940703264

Merged via the queue into NVIDIA:main with commit f2dcd42 Apr 25, 2026
67 of 68 checks passed
yangbofun pushed a commit to xlm-research/Megatron-LM that referenced this pull request May 22, 2026
Signed-off-by: qiyuw <qiyuw@nvidia.com>
Co-authored-by: Antoni-Joan Solergibert <asolergibert@nvidia.com>
yhgalaxy pushed a commit to yhgalaxy/Megatron-LM that referenced this pull request Jun 17, 2026
Signed-off-by: qiyuw <qiyuw@nvidia.com>
Co-authored-by: Antoni-Joan Solergibert <asolergibert@nvidia.com>
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
Signed-off-by: qiyuw <qiyuw@nvidia.com>
Co-authored-by: Antoni-Joan Solergibert <asolergibert@nvidia.com>
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
Signed-off-by: qiyuw <qiyuw@nvidia.com>
Co-authored-by: Antoni-Joan Solergibert <asolergibert@nvidia.com>
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5 participants