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fix: async_utils: explicit GC in persistent checkpoint worker loop#3591

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sbak5 merged 3 commits into
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sbak5:sbak/async_ckpt_gc
Feb 26, 2026
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fix: async_utils: explicit GC in persistent checkpoint worker loop#3591
sbak5 merged 3 commits into
NVIDIA:mainfrom
sbak5:sbak/async_ckpt_gc

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@sbak5 sbak5 commented Feb 25, 2026

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Drop references and run gc.collect() after each save item in PersistentAsyncCaller's worker to free memory sooner and avoid retaining large checkpoint buffers between iterations.

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Drop references and run gc.collect() after each save item in
PersistentAsyncCaller's worker to free memory sooner and avoid
retaining large checkpoint buffers between iterations.
@sbak5 sbak5 requested review from a team as code owners February 25, 2026 19:28
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This pull request requires additional validation before any workflows can run on NVIDIA's runners.

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@svcnvidia-nemo-ci svcnvidia-nemo-ci requested a review from a team February 25, 2026 19:28
@sbak5 sbak5 added complexity: low core_r0.16.0 Cherry-pick label for core_r0.16.0 release branch labels Feb 25, 2026
@ericharper ericharper added the Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. label Feb 25, 2026
@sbak5 sbak5 enabled auto-merge February 26, 2026 02:30
@sbak5

sbak5 commented Feb 26, 2026

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/ok to test 739db7a

@dimapihtar dimapihtar left a comment

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LGTM. Thank you!

@sbak5

sbak5 commented Feb 26, 2026

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/ok to test adda2cf

@sbak5 sbak5 added this pull request to the merge queue Feb 26, 2026
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🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/22450666010

Merged via the queue into NVIDIA:main with commit e1a9ac9 Feb 26, 2026
52 of 53 checks passed
@sbak5 sbak5 deleted the sbak/async_ckpt_gc branch February 26, 2026 17:24
ko3n1g pushed a commit that referenced this pull request Feb 26, 2026
ananthsub pushed a commit to ananthsub/Megatron-LM that referenced this pull request Mar 3, 2026
BoxiangW pushed a commit to BoxiangW/Megatron-LM that referenced this pull request Mar 4, 2026
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6 participants