*: optimize log puller performance under single large table scenario

[lidezhu]

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

Check List

Tests

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

Questions

Will it cause performance regression or break compatibility?

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[ti-chi-bot]

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[gemini-code-assist]

Summary of Changes

Hello @lidezhu, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This PR aims to optimize memory usage and potentially improve performance by refactoring parts of the log service's region event handling to eliminate direct reliance on heap-based data structures and operations. This change streamlines how resolved timestamps are managed within the system.

Highlights

• Heap Usage Reduction: The pull request refactors the region_event_handler.go file to avoid direct use of heap-based operations. Specifically, the UpdateLockedRangeStateHeap call is commented out, and GetHeapMinTs is replaced with ResolvedTs. This indicates a shift away from heap-dependent logic for managing resolved timestamps and locked range states.

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[gemini-code-assist]

Code Review

This pull request aims to avoid using a heap for calculating the minimum resolved timestamp in the log puller, which is a reasonable performance trade-off. The change comments out the heap update logic and replaces the heap-based timestamp retrieval with an iterative approach. My review includes a suggestion to remove the commented-out code instead of leaving it in, and points out that this change makes the heap-related data structures and methods in RangeLock largely obsolete. These should be cleaned up to improve maintainability and avoid running dead code.

[gemini-code-assist]

It's better to remove dead code rather than commenting it out. Since GetHeapMinTs is also being replaced, this suggests a move away from using the heap for calculating the minimum resolved timestamp. The heap-related logic in RangeLock now appears to be partially unused and could be removed entirely in this or a follow-up PR to clean up the code and avoid unnecessary operations (e.g., lockedRangeStateHeap in regionlock.RangeLock).

[ti-chi-bot]

[FORMAT CHECKER NOTIFICATION]

Notice: To remove the do-not-merge/needs-linked-issue label, please provide the linked issue number on one line in the PR body, for example: Issue Number: close #123 or Issue Number: ref #456.

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[ti-chi-bot]

@lidezhu: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-error-log-review	0c5f67c	link	true	/test pull-error-log-review
pull-check	0c5f67c	link	true	/test pull-check

Full PR test history. Your PR dashboard.

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