add permute fusion into hybrid ep by Autumn1998 · Pull Request #4089 · NVIDIA/Megatron-LM

Autumn1998 · 2026-04-01T05:17:02Z

What does this PR do ?

This PR introduce the new feature: fuse the permute/unpermute with the dispatch/combine into 1 kernel
This feature is provided by the hybrid-ep
related PR om dev: #4073

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github-actions · 2026-04-01T05:17:13Z

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Victarry

LGTM. Already reviewed in #4073

yashaswikarnati · 2026-04-07T17:55:07Z

-    moe_hybridep_num_sms: int = 16
-    """Number of SMs to use for HybridEP. In pure NVL scenarios,
-    16 SMs can generally achieve good bandwidth."""
+    moe_hybridep_num_sms: Optional[int] = None


nit; could we add the defaults used in the doc string here.

I'm not tend to do this, as the default number of SMs used on the hybrid EP side may change.

yaox12 · 2026-04-08T02:12:28Z

/ok to test 1f0733c

Autumn1998 · 2026-04-16T06:12:11Z

/ok to test e28bb0e

Autumn1998 · 2026-04-16T07:53:59Z

/ok to test e28bb0e

Autumn1998 · 2026-04-16T11:15:16Z

/ok to test d31d205

Autumn1998 · 2026-04-17T02:09:18Z

/ok to test d31d205

Autumn1998 · 2026-04-20T02:28:33Z

/ok to test d31d205

Autumn1998 · 2026-04-23T02:27:15Z

/ok to test d31d205

…e_fusion_main

Autumn1998 · 2026-04-23T05:49:24Z

/ok to test 022d94b

Autumn1998 · 2026-04-23T08:06:46Z

/ok to test 022d94b

Autumn1998 · 2026-04-24T02:35:55Z

/ok to test 022d94b

Victarry · 2026-04-24T07:19:00Z

/ok to test 139778d

svcnvidia-nemo-ci · 2026-04-28T00:47:34Z

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/25027627614

Co-authored-by: root <root@eos0047.eos.clusters.nvidia.com> Co-authored-by: root <root@eos0260.eos.clusters.nvidia.com> Co-authored-by: Dennis(Zhenhuan) Liu <denliu@nvidia.com>

add permute fusion into hybrid ep

f1eb3c6

Autumn1998 requested review from a team as code owners April 1, 2026 05:17

svcnvidia-nemo-ci marked this pull request as draft April 1, 2026 05:17

Autumn1998 mentioned this pull request Apr 1, 2026

[Dev] Add permute/unpermute fusion with dispatch/combine in Hybrid-EP #4073

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Autumn1998 marked this pull request as ready for review April 1, 2026 05:18

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svcnvidia-nemo-ci added the complexity: low label Apr 1, 2026

erhoo82 added dev2main: mbridge dev to main: this PR is needed in main for mbridge 26.04 Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. labels Apr 2, 2026

dingqingy-nv added the 26.04.01 label Apr 3, 2026

dingqingy-nv mentioned this pull request Apr 3, 2026

[perf] fix: set NUM_OF_TOKENS_PER_CHUNK_COMBINE_API=128 for all hybrid-ep recipes NVIDIA-NeMo/Megatron-Bridge#3135

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Phlip79 removed the Expert Review [deprecated] Apply this label to indicate that your PR is ready for expert review. label Apr 3, 2026

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svcnvidia-nemo-ci added the Final Review PR is in the "final review" stage label Apr 7, 2026

fix

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yashaswikarnati reviewed Apr 7, 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 7, 2026

yaox12 enabled auto-merge April 8, 2026 02:12

svcnvidia-nemo-ci added this to the Core 0.16 milestone Apr 8, 2026

Autumn1998 requested a review from a team as a code owner April 16, 2026 06:10

svcnvidia-nemo-ci removed the Approved All necessary approvals have been made label Apr 16, 2026

copy-pr-bot Bot temporarily deployed to test April 16, 2026 06:13 Inactive

fix mamba CI

d31d205

copy-pr-bot Bot temporarily deployed to test April 16, 2026 11:16 Inactive

Merge remote-tracking branch 'ADLR/main' into tongliu_hybridep_permut…

022d94b

…e_fusion_main

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Victarry enabled auto-merge April 24, 2026 06:27

Merge branch 'main' into tongliu_hybridep_permute_fusion_main

139778d

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yaox12 requested a review from Phlip79 April 27, 2026 02:46

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svcnvidia-nemo-ci added the Approved All necessary approvals have been made label Apr 28, 2026

Merged via the queue into NVIDIA:main with commit 8c5cf05 Apr 28, 2026
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sbhavani mentioned this pull request May 26, 2026

[ROADMAP][2026 Q2] Megatron Core Roadmap #4997

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Autumn1998 commented Apr 1, 2026

What does this PR do ?

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