logservice: bound scan lock by region end key

[tenfyzhong]

What problem does this PR solve?

Issue Number: close #4192

What is changed and how it works?

This PR adds an explicit scan boundary for lock resolving in logservice/txnutil/lock_resolver.go.

• Cache region EndKey together with StartKey when locating the region.
• Set ScanLockRequest.EndKey on every scan request.
• Keep lock scanning bounded to the target region to avoid returning out-of-region locks in boundary edge cases.

Check List

Tests

• Unit test

go test ./logservice/txnutil/...

Questions

Will it cause performance regression or break compatibility?

No. This only tightens scan range boundaries for existing region-scoped lock resolving.

Do you need to update user documentation, design documentation or monitoring documentation?

No.

Release note

None

Summary by CodeRabbit

• Bug Fixes
  • Improved lock scanning efficiency by properly constraining scan operations to appropriate region boundaries, preventing unnecessary checks beyond intended ranges.

[gemini-code-assist]

Summary of Changes

Hello @tenfyzhong, 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 pull request refines the lock resolution mechanism by introducing explicit scan boundaries. By caching and utilizing the region's end key, the system can more accurately constrain lock scan requests to their intended regions, thereby preventing the unintended return of out-of-region locks and enhancing the robustness of the transaction utility.

Highlights

• Explicit Scan Boundary: An explicit scan boundary has been added for lock resolving in logservice/txnutil/lock_resolver.go to ensure scans remain within the target region.
• Region EndKey Caching: The region's EndKey is now cached alongside its StartKey when locating a region, making it available for scan requests.
• Bounded Lock Scanning: The ScanLockRequest.EndKey is now explicitly set on every scan request, preventing out-of-region locks from being returned in boundary edge cases.

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Changelog

• logservice/txnutil/lock_resolver.go
  • Declared a new variable endKey to store the region's end key.
  • Populated the endKey variable with the loc.EndKey when locating a region.
  • Set the EndKey field of the ScanLockRequest using the newly cached endKey.

Activity

• No activity has been recorded for this pull request yet.

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[coderabbitai]

📝 Walkthrough

Walkthrough

This change adds explicit region boundary handling to the lock resolver's ScanLock requests. A new endKey variable tracks the region's end boundary, which is set during region flush and applied to each ScanLock request to prevent scanning locks outside the target region.

Changes

Cohort / File(s)	Summary
Lock Resolver Boundary Handling logservice/txnutil/lock_resolver.go	Introduces endKey variable initialized from region's EndKey and applies it as the scan boundary in ScanLock requests, ensuring locks are only scanned within the target region's bounds.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

Suggested labels

lgtm, approved, size/XS

Suggested reviewers

• asddongmen
• flowbehappy

Poem

🔐 A lock resolver, careful and wise,
Now bounds its scan with region-wise eyes,
No locks shall roam beyond the fence,
Defensive code—pure excellence! ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically describes the main change: adding a region end key boundary to scan lock operations.
Description check	✅ Passed	The description follows the template structure, includes linked issue number, explains the changes clearly, specifies test approach, and addresses all required sections.
Linked Issues check	✅ Passed	The code changes directly implement the requirement from issue #4192 by caching region EndKey and setting ScanLockRequest.EndKey to keep scans bounded to the target region.
Out of Scope Changes check	✅ Passed	All changes in lock_resolver.go are directly related to bounding scan lock requests by region end key, with no out-of-scope modifications detected.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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

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• Create PR with unit tests
• Post copyable unit tests in a comment

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[gemini-code-assist]

Code Review

This pull request correctly bounds the lock scanning process in the logservice to the specific region's boundaries by utilizing the EndKey from the region's location cache. The changes in logservice/txnutil/lock_resolver.go are straightforward: a new variable endKey is introduced, populated with the region's end key, and then used to set the EndKey on the ScanLockRequest. This is a valuable correctness fix that prevents the lock resolver from scanning beyond the intended region, especially in boundary cases. The implementation is clean and I have no suggestions for improvement.

[tenfyzhong]

/test light

[tenfyzhong]

/test heavy

[tenfyzhong]

/retest

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: 3AceShowHand, lidezhu

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Details

Needs approval from an approver in each of these files:

• OWNERS [3AceShowHand,lidezhu]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2026-02-11 09:38:47.411257014 +0000 UTC m=+11280.491247709: ☑️ agreed by 3AceShowHand.
• 2026-02-11 12:06:45.006680716 +0000 UTC m=+20158.086671411: ☑️ agreed by lidezhu.

[ti-chi-bot]

@tenfyzhong: 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-cdc-pulsar-integration-heavy-next-gen	afa0b4d	link	unknown	/test pull-cdc-pulsar-integration-heavy-next-gen
pull-cdc-pulsar-integration-heavy	afa0b4d	link	unknown	/test pull-cdc-pulsar-integration-heavy

Full PR test history. Your PR dashboard.

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