[https://nvbugs/5351244][fix] CHERRY-PICK test_mpi_session (#7501)

[Superjomn]

Summary by CodeRabbit

• Tests
  • Re-enabled the remote MPI session test to run in CI.
  • Updated the test to dynamically resolve the helper script path and validate its presence.
  • Standardized subprocess invocation with explicit environment, I/O piping, buffering, session handling, and working directory for more stable execution.
  • Continued passing the task type argument to the script to preserve behavior.
  • No changes to public APIs.

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Test Coverage

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[Superjomn]

/bot run

[Superjomn]

/bot run --extra-stages "A100X-TensorRT-[Post-Merge]-3"

[tensorrt-cicd]

PR_Github #19527 [ run ] triggered by Bot

[tensorrt-cicd]

PR_Github #19528 Bot args parsing error: usage: /bot [-h]
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[Superjomn]

/bot run --extra-stage "A100X-TensorRT-[Post-Merge]-3"

[tensorrt-cicd]

PR_Github #19531 [ run ] triggered by Bot

[tensorrt-cicd]

PR_Github #19527 [ run ] completed with state ABORTED
LLM/main/L0_MergeRequest_PR #14678 (Blue Ocean) completed with status: ABORTED

[coderabbitai]

📝 Walkthrough

Walkthrough

The unit test test_remote_mpi_session in tests/unittest/llmapi/test_mpi_session.py was unskipped and updated to resolve the shell script path dynamically. The test now asserts the script’s existence, runs it with expanded subprocess.Popen parameters, sets cwd to the script’s directory, and still passes task_type as an argument.

Changes

Cohort / File(s)	Summary
Unit tests — MPI session tests/unittest/llmapi/test_mpi_session.py	Unskip test; compute absolute path to _test_remote_mpi_session.sh, assert existence; invoke via subprocess with explicit env, stdout/stderr pipes, buffering, start_new_session, universal_newlines, and cwd; continue passing task_type to the script.

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant PyTest as PyTest
  participant Test as test_mpi_session.py
  participant Shell as _test_remote_mpi_session.sh

  PyTest->>Test: run test_remote_mpi_session
  Test->>Test: resolve script path<br/>assert exists
  Test->>Shell: subprocess.Popen(cmd, env, cwd, pipes, start_new_session)
  Shell-->>Test: stdout/stderr, exit code
  Test-->>PyTest: assertions on result

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Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description Check	⚠️ Warning	The PR description is essentially the unfilled repository template (including the @coderabbitai placeholder) and omits a concrete Description, Test Coverage, and checklist details, so it does not explain what changed or why. The raw_summary shows specific edits to tests/unittest/llmapi/test_mpi_session.py (removing a skip, resolving the script path, and expanding Popen arguments) but none of these are documented in the body. As written, reviewers cannot assess intent, risk, or whether tests sufficiently cover the change.	Replace the template placeholders with a concise Description that summarizes the actual changes and rationale (mention the removed skip, script path resolution, and Popen argument changes), add a Test Coverage section listing the relevant tests and how to run them, confirm PR Checklist items (including any CODEOWNERS or dependency notes), and optionally link to the original PR #7501 and NVBugs entry for context.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The PR title "[https://nvbugs/5351244][fix] CHERRY-PICK test_mpi_session (#7501)" uses the repository's NVBugs format and [fix] type and clearly identifies the primary change as a cherry-pick of the test_mpi_session update, which matches the changes in tests/unittest/llmapi/test_mpi_session.py. It is concise and meaningful for reviewers scanning history. Minor noise (uppercase "CHERRY-PICK" and the parenthetical original PR number) does not make the title misleading.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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[coderabbitai]

Actionable comments posted: 1

🧹 Nitpick comments (1)

tests/unittest/llmapi/test_mpi_session.py (1)

66-73: Consider removing redundant cwd parameter.

The cwd parameter on line 73 duplicates the path resolution already done on line 61. Since test_file already contains the full path, the cwd parameter is unnecessary.

Apply this diff to remove the redundant parameter:

    with Popen(command,
               env=os.environ,
               stdout=PIPE,
               stderr=PIPE,
               bufsize=1,
               start_new_session=True,
-               universal_newlines=True,
-               cwd=os.path.dirname(os.path.abspath(__file__))) as process:
+               universal_newlines=True) as process:

📜 Review details

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📥 Commits

Reviewing files that changed from the base of the PR and between ab26d21 and 660cb46.

📒 Files selected for processing (1)

• tests/unittest/llmapi/test_mpi_session.py (1 hunks)

🧰 Additional context used

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🔇 Additional comments (1)

tests/unittest/llmapi/test_mpi_session.py (1)

60-63: LGTM! Robust script path resolution and validation.

The changes improve the test by dynamically resolving the script path and verifying its existence before execution. This makes the test more maintainable and provides clear error messages if the script is missing.

[tensorrt-cicd]

PR_Github #19531 [ run ] completed with state FAILURE
/LLM/main/L0_MergeRequest_PR pipeline #14680 completed with status: 'FAILURE'

[Superjomn]

/bot run --extra-stage "A100X-TensorRT-Post-Merge-3"

[tensorrt-cicd]

PR_Github #19544 [ run ] triggered by Bot

[tensorrt-cicd]

PR_Github #19544 [ run ] completed with state SUCCESS
/LLM/main/L0_MergeRequest_PR pipeline #14690 completed with status: 'SUCCESS'