add is_torch_min_version in fsdp src by xrennvidia · Pull Request #4812 · NVIDIA/Megatron-LM

xrennvidia · 2026-05-15T02:36:29Z

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To fix this FSDP wheel building issue.

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Signed-off-by: Xiaowei Ren <xren@nvidia.com>

copy-pr-bot · 2026-05-15T02:36:33Z

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github-actions · 2026-05-15T02:36:38Z

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chtruong814 · 2026-05-15T03:13:34Z

/ok to test f9b1a20

cspades

LGTM, I made a similar change in my CG PR where I will remove the MCore import from DDPConfig but I like this better, just have a util for it.

ericharper · 2026-05-15T19:56:17Z

 import torch

-from megatron.core.utils import is_torch_min_version
+from .utils import is_torch_min_version


can we use a full path?

There's two possible paths depending on the install:

megatron.core.distributed.fsdp.src.megatron_fsdp.utils megatron_fsdp.utils

jaredcasper · 2026-05-15T20:08:02Z

+    _torch_version = PkgVersion(torch.__version__)
+except Exception:
+    # This is a WAR for building docs, where torch is not actually imported
+    _torch_version = PkgVersion("0.0.0")


Will this lead to weird error messages where it says torch is too old when in fact it isn't even installed?

Phlip79 · 2026-05-17T03:23:29Z

/ok to test 0238c1b

svcnvidia-nemo-ci · 2026-05-17T06:46:31Z

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/25983840395

* origin/main: (138 commits) Refactor CUDA graph API: decompose cuda_graph_scope into full_iteration impl, inference scope, and per-layer capture modules (NVIDIA#4292) Add high-priority A2A stream and HybridEP preprocessing SMs (NVIDIA#4694) add is_torch_min_version in fsdp src (NVIDIA#4812) [Main][feat] Support A2A Overlap for Megatron-FSDP (NVIDIA#3797) Reorder mtp_post_process after attention backward in 1F1B schedule plan (NVIDIA#4695) [fix] Use MSC for checking checkpoint existence (NVIDIA#4251) Combine GEMM + SwiGLU fused MLP PRs (3890, 4071, 4095, 4219, 4311, 4324) → main (NVIDIA#4636) Strengthen test_checkpoint to verify distributed checkpoint behavior (NVIDIA#4711) Disable MSC by default; opt in via --enable-msc (NVIDIA#4629) additional tests for nvrx (NVIDIA#4522) Update copy-pr-bot.yaml [skip ci] ci: tolerate git-gc race in /home/runner chown after checkout (NVIDIA#4808) Inference: Optimize Prefill Engine Steps for Nemotron (NVIDIA#4764) chore: Update nightly tests golden values (NVIDIA#4805) ci: Update workflow to use same commit for building docker image and running tests (NVIDIA#4787) Update owners (NVIDIA#4794) Bump nvidia-modelopt>=0.44.0 (NVIDIA#4803) fix tokenizers in respect to newer transformers (NVIDIA#4608) Use Protocols to type-check linear_proj submodules of Attention (NVIDIA#3434) Fix recompute checkpointing + training CGs (NVIDIA#3919) ... # Conflicts: # megatron/core/transformer/moe/moe_utils.py

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com>

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com> Signed-off-by: yhgalaxy <yhgalaxy@outlook.com>

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com> Signed-off-by: Jon Barker <jbarker@aws-cmh-slurm-1-vscode-02.cm.cluster>

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com>

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com> Signed-off-by: Dmytro Pykhtar <dpykhtar@nvidia.com>

add is_torch_min_version in fsdp src

f9b1a20

Signed-off-by: Xiaowei Ren <xren@nvidia.com>

xrennvidia requested review from a team as code owners May 15, 2026 02:36

svcnvidia-nemo-ci marked this pull request as draft May 15, 2026 02:36

xrennvidia marked this pull request as ready for review May 15, 2026 02:43

svcnvidia-nemo-ci requested a review from a team May 15, 2026 02:44

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chtruong814 approved these changes May 15, 2026

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svcnvidia-nemo-ci added the Final Review PR is in the "final review" stage label May 15, 2026

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Merge branch 'main' into xren/nccl_ub_fix_for_fsdp

0238c1b

Phlip79 enabled auto-merge May 17, 2026 03:23

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Phlip79 added this pull request to the merge queue May 17, 2026

Merged via the queue into NVIDIA:main with commit 7371e01 May 17, 2026
78 checks passed

xrennvidia deleted the xren/nccl_ub_fix_for_fsdp branch May 18, 2026 03:03

janEbert pushed a commit to janEbert/Megatron-LM that referenced this pull request Jun 2, 2026

add is_torch_min_version in fsdp src (NVIDIA#4812)

18150a3

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com>

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

add is_torch_min_version in fsdp src (NVIDIA#4812)

5f7a407

Signed-off-by: Xiaowei Ren <xren@nvidia.com> Co-authored-by: Philip Petrakian <ppetrakian@nvidia.com>

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add is_torch_min_version in fsdp src - #4812

add is_torch_min_version in fsdp src#4812
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xrennvidia commented May 15, 2026 •

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