sink(refactor): Refine functions and improve event splitting code (#2367)

[ti-chi-bot]

This is an automated cherry-pick of #2367

What problem does this PR solve?

ref: #2301

What is changed and how it works?

Refine functions and improve event splitting code.

Check List

Tests

• Unit test
• Integration test

Code changes

None

Side effects

None

Related changes

• Need to cherry-pick to the release branch

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has not been approved.

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

The full list of commands accepted by this bot can be found here.

Reviewer can indicate their review by submitting an approval review.
Reviewer can cancel approval by submitting a request changes review.

[amyangfei]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 80efb8a

[amyangfei]

/run-unit-tests
/run-leak-tests

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (release-5.1@02ae750). Click here to learn what that means.
The diff coverage is n/a.

❗ Current head 80efb8a differs from pull request most recent head 6b1c1d1. Consider uploading reports for the commit 6b1c1d1 to get more accurate results

@@               Coverage Diff                @@
##             release-5.1      #2399   +/-   ##
================================================
  Coverage               ?   57.1046%           
================================================
  Files                  ?        165           
  Lines                  ?      19445           
  Branches               ?          0           
================================================
  Hits                   ?      11104           
  Misses                 ?       7281           
  Partials               ?       1060           

[ti-chi-bot]

@ti-chi-bot: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

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.