metrics: set sync load latency as P9999

[hawkingrei]

What problem does this PR solve?

Issue Number: close #56980

Problem Summary:

What changed and how does it work?

The current sync load monitoring primarily focuses on P95 latency, which is insufficient for capturing extreme timeout issues. While P95 latency may not indicate a timeout, P9999 latency could be significantly high, leading to potential misjudgments and overlooked performance issues.

Check List

Tests

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

  • I checked and no code files have been changed.

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

Please refer to Release Notes Language Style Guide to write a quality release note.

Enhanced sync load monitoring to include P9999 latency metrics for better detection and analysis of extreme performance issues

对 sync load 监控改为P9999，更好的观察性能问题

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 56.2922%. Comparing base (390de88) to head (fa9629d).
Report is 6 commits behind head on master.

Additional details and impacted files

@@                Coverage Diff                @@
##             master     #56981         +/-   ##
=================================================
- Coverage   73.2941%   56.2922%   -17.0019%     
=================================================
  Files          1638       1764        +126     
  Lines        453785     632687     +178902     
=================================================
+ Hits         332598     356154      +23556     
- Misses       100814     252495     +151681     
- Partials      20373      24038       +3665     

Flag	Coverage Δ
integration	37.0128% <ø> (?)
unit	72.5053% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.9478% <ø> (ø)
parser	∅ <ø> (∅)
br	52.6628% <ø> (+6.6639%)	⬆️

[lance6716]

/hold

not sure metrics change should also ask PM's opinion. Feel free to unhold

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-10-30 03:52:44.866820808 +0000 UTC m=+408277.705976347: ☑️ agreed by xhebox.
• 2024-10-30 03:56:37.9633161 +0000 UTC m=+408510.802471644: ☑️ agreed by lance6716.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: AilinKid, lance6716, xhebox

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Details

Needs approval from an approver in each of these files:

• OWNERS [AilinKid,lance6716,xhebox]

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[hawkingrei]

/unhold

[hawkingrei]

/cherrypick release-8.1
/cherrypick release-7.5

[ti-chi-bot]

@hawkingrei: new pull request created to branch release-7.5: #57000.

Details

In response to this:

/cherrypick release-8.1
/cherrypick release-7.5

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[ti-chi-bot]

@hawkingrei: new pull request created to branch release-8.1: #57001.

Details

In response to this:

/cherrypick release-8.1
/cherrypick release-7.5

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.