Stream: git-wasmtime

Topic: wasmtime / PR #12412 Don't pass module into `initialize_v...

Wasmtime GitHub notifications bot (Jan 23 2026 at 20:24):

fitzgen opened PR #12412 from fitzgen:dont-pass-module-to-initialize-vmctx to bytecodealliance:main:

Get it from self, which means we can't ever pass in the wrong module.

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Wasmtime GitHub notifications bot (Jan 23 2026 at 20:24):

fitzgen requested dicej for a review on PR #12412.

Wasmtime GitHub notifications bot (Jan 23 2026 at 20:24):

fitzgen requested wasmtime-core-reviewers for a review on PR #12412.

Wasmtime GitHub notifications bot (Jan 23 2026 at 20:30):

alexcrichton submitted PR review:

The purpose of this is to avoid the Arc::clone which can be pretty hotly contested here since if many threads instantiate the same module/component that'll cause lots of incs/decs on the same memory location. Historically I don't recall this being a problem here exactly, but we have at least one bug report showing a 30% slowdown in throughput for an optimized host function if we include an Arc::clone by accident.

Instead of a clone, however, how about something like what components do?

Wasmtime GitHub notifications bot (Jan 23 2026 at 21:02):

fitzgen updated PR #12412.

Wasmtime GitHub notifications bot (Jan 23 2026 at 21:02):

fitzgen requested alexcrichton for a review on PR #12412.

Wasmtime GitHub notifications bot (Jan 23 2026 at 21:11):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Jan 23 2026 at 21:38):

fitzgen added PR #12412 Don't pass module into initialize_vmctx to the merge queue

Wasmtime GitHub notifications bot (Jan 23 2026 at 22:00):

fitzgen merged PR #12412.

Wasmtime GitHub notifications bot (Jan 23 2026 at 22:00):

fitzgen removed PR #12412 Don't pass module into initialize_vmctx from the merge queue

Last updated: Jan 29 2026 at 13:25 UTC