[TRTLLM-8374][fix] workaround disagg MMLU test failures

[ixlmar]

Description

This should unblock other PRs by fixing multi-GPU test failures seen in #8046.

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Summary by CodeRabbit

• Bug Fixes
  • Ensures deterministic generations during MMLU evaluation by using a fixed temperature, reducing run-to-run variability in results.
• Tests
  • Standardizes evaluation settings for MMLU to produce more consistent and reproducible scores across test runs.

[ixlmar]

/bot run --only-multi-gpu-test

[tensorrt-cicd]

PR_Github #20360 [ run ] triggered by Bot

[ixlmar]

Note: This change partially reverts #7909

[coderabbitai]

📝 Walkthrough

Walkthrough

Updated MMLU evaluation to pass a temperature parameter as a dict {"temperature": 0} when yielding samples, replacing the previous None value. No other logic, declarations, or control flow changes.

Changes

Cohort / File(s)	Summary of Changes
MMLU evaluation param change tensorrt_llm/evaluate/mmlu.py	Replace yielded temperature argument from None to {"temperature": 0} to set fixed generation temperature for test prompts.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Pre-merge checks and finishing touches

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description Check	⚠️ Warning	The PR description includes the high-level goal in the Description section but omits details of the implemented workaround and leaves the Test Coverage section untouched with only the template comment. Because it neither explains the solution approach nor lists relevant tests, it does not meet the required template completeness.	Please expand the Description to summarize how the code change implements the workaround (e.g., setting a fixed temperature dict) and populate the Test Coverage section with specific test cases or suites that validate the new behavior.
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The title follows the required ticket format and specifies that this change addresses disaggregated multi-GPU MMLU test failures, which matches the pull request’s main objective of applying a workaround for those failures. It is concise, clear, and directly related to the core change without extraneous detail.

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• tensorrt_llm/evaluate/mmlu.py (1 hunks)

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🔇 Additional comments (2)

tensorrt_llm/evaluate/mmlu.py (2)

27-27: Verify whether the NVIDIA copyright year should be updated.

The NVIDIA copyright notice shows 2023, but this PR introduces changes in 2025. According to coding guidelines, the copyright header should include the current year when source files are modified.

Please confirm whether the copyright year should be updated to include 2025, given that this change is being made in September 2025.

---

222-222: Evaluator supports per-sample sampling_args; passing {"temperature": 0} is correct.
evaluate() merges any keys in sampling_args into a SamplingParams instance (via _get_sampline_params), so this enforces greedy (temperature=0) decoding and yields deterministic outputs—explaining why it fixes the multi-GPU MMLU test instability. No further changes required.

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[tensorrt-cicd]

PR_Github #20360 [ run ] completed with state SUCCESS
/LLM/main/L0_MergeRequest_PR pipeline #15359 (Partly Tested) completed with status: 'FAILURE'

[ixlmar]

/bot run --only-multi-gpu-test

[ixlmar]

/bot run --only-multi-gpu-test --disable-fail-fast

[tensorrt-cicd]

PR_Github #20375 [ run ] triggered by Bot

[tensorrt-cicd]

PR_Github #20376 [ run ] triggered by Bot

[tensorrt-cicd]

PR_Github #20375 [ run ] completed with state ABORTED

[tensorrt-cicd]

PR_Github #20376 [ run ] completed with state SUCCESS
/LLM/main/L0_MergeRequest_PR pipeline #15371 (Partly Tested) completed with status: 'FAILURE'

[ixlmar]

/bot run --only-multi-gpu-test --disable-fail-fast

[ixlmar]

/bot kill

[tensorrt-cicd]

PR_Github #20399 [ run ] triggered by Bot

[ixlmar]

Superseded by #8103

[tensorrt-cicd]

PR_Github #20401 [ ] completed with state FAILURE
Not allowed on merged PR

[tensorrt-cicd]

PR_Github #20399 [ run ] completed with state SUCCESS
/LLM/main/L0_MergeRequest_PR pipeline #15393 (Partly Tested) completed with status: 'FAILURE'