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.

[Rustin170506]

/run-all-tests

[codecov-commenter]

Codecov Report

Merging #2397 (240b98b) into release-4.0 (753073a) will increase coverage by 1.6652%.
The diff coverage is 57.7319%.

@@                 Coverage Diff                 @@
##           release-4.0      #2397        +/-   ##
===================================================
+ Coverage      53.7661%   55.4313%   +1.6651%     
===================================================
  Files              153        165        +12     
  Lines            15958      19590      +3632     
===================================================
+ Hits              8580      10859      +2279     
- Misses            6475       7684      +1209     
- Partials           903       1047       +144     

[amyangfei]

/merge

[ti-chi-bot]

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

Commit hash: 1ca0695