[https://nvbugs/6463819][fix] Replace the concrete-type guard with the polymorphic base-class predicate `not…

[trtllm-agent]

Summary

• Root cause: tests/test_common/session_reuse.py rebinds proxy.MpiPoolSession to a factory function so isinstance(x, MpiPoolSession) at line 576 gets a function as its second arg and raises TypeError.
• Fix: Replace the concrete-type guard with the polymorphic base-class predicate not self.mpi_session.is_comm_session() — same semantics (pool sessions register PIDs; comm sessions skip), works through the wrapper, and no debug/TODO markers introduced.
• Automated fix generated by repair-bot

Test plan

• Verify fix on the same GPU type as the original failure
• Check for regressions in related tests

Links

• Bug: https://nvbugs/6463819

Summary by CodeRabbit

• Bug Fixes

  • Improved worker readiness detection across supported session types, helping processes register correctly for monitoring.

• Tests

  • Re-enabled an end-to-end beam search test that was previously waived.

[coderabbitai]

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 4277d15 and c48e03f.

📒 Files selected for processing (2)

• tensorrt_llm/executor/proxy.py
• tests/integration/test_lists/waives.txt

💤 Files with no reviewable changes (1)

• tests/integration/test_lists/waives.txt

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📝 Walkthrough

Walkthrough

The executor proxy now uses a session-type predicate when parsing worker readiness, while retaining the three-element status requirement. The related beam-search integration test waiver was removed.

Changes

Worker readiness handling

Layer / File(s)	Summary
Session predicate and integration coverage tensorrt_llm/executor/proxy.py, tests/integration/test_lists/waives.txt	Worker identity extraction now applies to non-communication sessions with three-element status data, and the corresponding beam-search test is no longer waived.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• NVIDIA/TensorRT-LLM#16489: Adjusts the same readiness-status gating logic for worker identity registration.
• NVIDIA/TensorRT-LLM#16490: Replaces the concrete MPI session check with a session predicate in the same function.
• NVIDIA/TensorRT-LLM#16492: Changes the same three-element status handling and worker PID registration condition.

Suggested reviewers: dpitman-nvda

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title matches the main fix and includes the NVBugs ID and fix type.
Description check	✅ Passed	The description explains the bug, fix, and test plan, though it uses custom headings instead of the template's exact sections.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[brnguyen2]

Superseded by #16444, which has merged.