eventstore: improve compress&decompress speed by reusing buffer

[lidezhu]

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

This pull request focuses on optimizing the performance of ZSTD compression and decompression within the event store. By implementing a strategy to reuse byte buffers for these operations, the changes aim to significantly reduce memory allocation overhead and improve the speed and efficiency of event processing, both when writing and reading compressed data.

Highlights

• ZSTD Compression Buffer Reuse: The writeEvents function now utilizes a reusable byte buffer for ZSTD compression operations. This change aims to reduce memory allocations and improve performance during event writing by avoiding repeated buffer creation.
• ZSTD Decompression Buffer Reuse: Similarly, the eventStoreIter has been enhanced to reuse a byte buffer for ZSTD decompression. This optimization minimizes memory allocations during event iteration and reading, contributing to overall efficiency.
• New Test Case for Buffer Reuse: A new unit test, TestEventStoreCompressionAndIterDecodeBufferReuse, has been added. This test specifically validates the correctness of the buffer reuse logic for both compression and decompression, ensuring data integrity and non-mutation.

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?

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

Release note

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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 pull request focuses on optimizing the performance of ZSTD compression and decompression within the event store. By implementing a strategy to reuse byte buffers for these operations, the changes aim to significantly reduce memory allocation overhead and improve the speed and efficiency of event processing, both when writing and reading compressed data.

Highlights

• ZSTD Compression Buffer Reuse: The writeEvents function now utilizes a reusable byte buffer for ZSTD compression operations. This change aims to reduce memory allocations and improve performance during event writing by avoiding repeated buffer creation.
• ZSTD Decompression Buffer Reuse: Similarly, the eventStoreIter has been enhanced to reuse a byte buffer for ZSTD decompression. This optimization minimizes memory allocations during event iteration and reading, contributing to overall efficiency.
• New Test Case for Buffer Reuse: A new unit test, TestEventStoreCompressionAndIterDecodeBufferReuse, has been added. This test specifically validates the correctness of the buffer reuse logic for both compression and decompression, ensuring data integrity and non-mutation.

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[gemini-code-assist]

Code Review

This pull request aims to improve compression and decompression speed by reusing buffers. The changes involve modifying writeEvents to accept a reusable compression buffer and updating eventStoreIter to reuse a decompression buffer. The implementation for buffer reuse in both compression and decompression appears correct and safe. The logic correctly handles buffer resizing and resetting for subsequent uses. The tests have been updated accordingly, and a new test has been added to verify the safety of buffer reuse in the iterator, which is a good addition. Overall, the changes are well-implemented and should achieve the intended performance improvement.

[asddongmen]

Is there a bench result?

[lidezhu]

Is there a bench result?

Working on it.

[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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