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Bad MemoryPool performance for large items in ReleaseSafe. #35627

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opened 2026年06月04日 20:01:53 +02:00 by psznm · 0 comments

psznm commented

2026年06月04日 20:01:53 +02:00

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Zig Version

0.16.0

Steps to Reproduce, Observed Behavior, and Expected Behavior

MemoryPool runs ptr.* = undefined; both on create and destroy, and there is no way to opt-out of it. This is a big issue, when one wants to use memory pool as fast access to larger storage, as it can easily become performance bottleneck (again, without a way to opt-out of it).

Also see https://ziggit.dev/t/releasesafe-slower-than-debug-and-performance-degrading-with-larger-buffers/15916/11

### Zig Version 0.16.0 ### Steps to Reproduce, Observed Behavior, and Expected Behavior MemoryPool runs `ptr.* = undefined;` both on create and destroy, and there is no way to opt-out of it. This is a big issue, when one wants to use memory pool as fast access to larger storage, as it can easily become performance bottleneck (again, without a way to opt-out of it). Also see https://ziggit.dev/t/releasesafe-slower-than-debug-and-performance-degrading-with-larger-buffers/15916/11

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2026年06月04日 20:01:53 +02:00

psznm referenced this issue from a pull request that will close it,

2026年06月04日 20:10:54 +02:00

Add unsafe variants to .create and .destroy of MemoryPool #35628

alexrp added

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2026年06月09日 11:46:38 +02:00

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