Signed-off-by: Bugen Zhao i@bugenzhao.comI hereby agree to the terms of the RisingWave Labs, Inc. Contributor License Agreement.

What's changed and what's your intention?

rkyv is a powerful library that enables zero-copy deserializing for arbitrary Rust types, which seems to be a good solution to #20017.

The main idea is, each type will have a corresponding Archived type. When a value is serialized into bytes with rkyv (which still incurs costs), the byte slice can then be directly interpreted as (transmuted into) a value in Archived type, with all fields are all in their Archived types. The Archived types are more like a view to the raw underlying serialized bytes, where we can easily access fields and perform operations just like on the original type.

Here's a demo:

https://github.com/BugenZhao/rust-playground/blob/1f42803c5697710aba2ff7980787e16268b62051/src/bin/rkyv_test.rs

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• I have checked the Release Timeline and Currently Supported Versions to determine which release branches I need to cherry-pick this PR into.

Documentation

• My PR needs documentation updates.