Reduce/downgrade some MPPTask logs (#10821)

[ti-chi-bot]

This is an automated cherry-pick of #10821

What problem does this PR solve?

Issue Number: close #10820

Problem Summary:

What is changed and how it works?

Reduce some MPPTask logs

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

None

Summary by CodeRabbit

• Chores
  • Reduced noisy info-level logs to debug for task start and completion messages.
  • Added timing around task unregistration and escalate to info for slow operations.
  • Made task start logging conditional based on measured pre-run time to reduce verbosity.
  • Ensured completion logs default to debug and only escalate on failure or non-successful status.

[ti-chi-bot]

@gengliqi This PR has conflicts, I have hold it.
Please resolve them or ask others to resolve them, then comment /unhold to remove the hold label.

[ti-chi-bot]

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 42c25021-24ee-46f3-a06a-02c36358c881

📥 Commits

Reviewing files that changed from the base of the PR and between d84d06b and ebc78d1.

📒 Files selected for processing (1)

• dbms/src/Flash/Mpp/MPPTask.cpp

💤 Files with no reviewable changes (1)

• dbms/src/Flash/Mpp/MPPTask.cpp

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📝 Walkthrough

Walkthrough

Log levels were reduced in MPPHandler and MPPTask; startup and unregister paths now measure elapsed time and only escalate logs to INFO when durations exceed thresholds; post-execution logging is initialized to DEBUG before conditional escalation.

Changes

MPP task logging optimization

Layer / File(s)	Summary
Simple log level downgrades dbms/src/Flash/Mpp/MPPHandler.cpp, dbms/src/Flash/Mpp/MPPTask.cpp	Handler completion log and destructor "finish MPPTask" message downgraded from LOG_INFO to LOG_DEBUG.
Performance-aware conditional logging dbms/src/Flash/Mpp/MPPTask.cpp	unregisterTask() measures unregistration duration and logs INFO for slow operations (DEBUG otherwise); task startup computes combined pre-run time and logs at INFO only if above threshold; post-execution log level is reset to DEBUG before conditional escalation.

🎯 2 (Simple) | ⏱️ ~8 minutes

• Possibly related PRs:

  • pingcap/tiflash#10821: Related changes that also downgrade MPP logging and introduce timing-based log level adjustments.

• Suggested reviewers:

  • windtalker
  • xzhangxian1008

"I nibble noisy logs away,
timing each hop and run,
quick hops hush to little squeaks,
slow ones shine in sun. 🐇✨"

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 20.00% 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 clearly summarizes the main change: downgrading/reducing MPPTask logs, which matches the code changes that downgrade log levels from INFO to DEBUG.
Description check	✅ Passed	The description follows the required template with all major sections populated including problem statement, changes summary, test checklist, and release notes, though the problem summary section is empty.
Linked Issues check	✅ Passed	The PR successfully addresses the objective from issue #10820 to reduce MPPTask logs by downgrading log levels in MPPHandler.cpp and MPPTask.cpp from INFO to DEBUG.
Out of Scope Changes check	✅ Passed	All code changes are scoped to reducing log verbosity in MPPTask-related files with no unrelated modifications present.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

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[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@dbms/src/Flash/Mpp/MPPTask.cpp`:
- Around line 586-591: The file contains unresolved Git conflict markers in
MPPTask::~MPPTask() and in runImpl() around the log-level setup — remove the
conflict markers (<<<<<<<, =======, >>>>>>>) and choose the correct code path:
in runImpl() ensure the log_level variable is properly declared/assigned
(restore either "auto log_level = Poco::Message::PRIO_DEBUG;" or the existing
"log_level = Poco::Message::PRIO_DEBUG;" depending on surrounding scope) and in
the destructor MPPTask::~MPPTask() pick and keep the intended implementation
block, deleting the alternate branch and markers so the file compiles cleanly;
search for MPPTask::~MPPTask and MPPTask::runImpl to locate and fix both hunks.
- Around line 155-159: There are unresolved merge conflict markers in MPPTask:
remove the conflict markers from MPPTask::~MPPTask and keep only LOG_DEBUG(log,
"finish MPPTask: {}", id.toString());, and in MPPTask::runImpl remove the
conflict markers so that only the intended single logging/code path remains
(ensure the consolidated use of the chosen log_level/logging statements in
runImpl rather than duplicated/conflicting branches); update both locations by
deleting the <<<<<<< / ======= / >>>>>>> lines and resulting dead code so the
file compiles cleanly.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 61f9b77c-0818-4e3e-80bd-37cb2050ccc5

📥 Commits

Reviewing files that changed from the base of the PR and between 2560b3d and 770001a.

📒 Files selected for processing (2)

• dbms/src/Flash/Mpp/MPPHandler.cpp
• dbms/src/Flash/Mpp/MPPTask.cpp

[windtalker]

lgtm

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: gengliqi, windtalker

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Needs approval from an approver in each of these files:

• OWNERS [gengliqi,windtalker]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2026-05-29 05:53:11.063809845 +0000 UTC m=+590661.033974896: ☑️ agreed by gengliqi.
• 2026-05-29 05:56:21.428269648 +0000 UTC m=+590851.398434710: ☑️ agreed by windtalker.