schemaStore: clear tableInfoItem in gc

[wk989898]

What problem does this PR solve?

Issue Number: close #4144

What is changed and how it works?

Check List

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[gemini-code-assist]

Summary of Changes

Hello @wk989898, 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 addresses issue #4144 by enhancing the garbage collection mechanism within the versionedTableInfoStore. The change ensures that outdated tableInfoItem instances are explicitly cleared during garbage collection, contributing to better memory management and resource utilization.

Highlights

• Garbage Collection Improvement: This PR modifies the gc function in multi_version.go to explicitly clear the tableInfoItem in the garbage collection process. This likely aims to free up memory and prevent potential memory leaks by ensuring that references to older table information are properly released.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Changelog

• logservice/schemastore/multi_version.go
  • Modified the gc function to include clear(v.infos[:target-1]) to explicitly clear the table info items during garbage collection.

Activity

• The PR addresses issue Possible memory leak in versionedTableInfoStore #4144.
• The PR includes a unit test (inferred from the checklist).

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Code Review

The pull request correctly implements a memory optimization in the gc method of versionedTableInfoStore. By using the clear built-in to zero out the prefix of the infos slice before reslicing, it prevents a common memory leak scenario in Go where the underlying array of a slice retains references to objects that are no longer accessible through the slice. This is particularly important for the TableInfo objects used here, as they are associated with resources that should be released when no longer needed. The logic is sound and follows idiomatic Go practices for version 1.21 and later.