Stream: git-wasmtime

Topic: wasmtime / PR #3760 Make memfd image creation lazy (on fi...

Wasmtime GitHub notifications bot (Feb 02 2022 at 23:59):

cfallin opened PR #3760 from memfd-lazy-create to main:

As a followup to the recent memfd allocator work, this PR makes the
memfd image creation occur on the first instantiation, rather than
immediately when the Module is loaded.

This shaves off a potentially surprising cost spike that would have
otherwise occurred: prior to the memfd work, no allocator eagerly read
the module's initial heap state into RAM. The behavior should now more
closely resemble what happened before (and the improvements in overall
instantiation time and performance, as compared to either eager init
with pure-mmap memory or user-mode pagefault handling with uffd,
remain).

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Wasmtime GitHub notifications bot (Feb 02 2022 at 23:59):

cfallin requested alexcrichton for a review on PR #3760.

Wasmtime GitHub notifications bot (Feb 03 2022 at 15:21):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Feb 03 2022 at 15:21):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Feb 03 2022 at 15:21):

alexcrichton created PR review comment:

Given the relative cost of locking a mutex I think it'd be better to use a OnceCell for this which also removes the need for cloning and a custom enum here.

Wasmtime GitHub notifications bot (Feb 03 2022 at 20:40):

cfallin updated PR #3760 from memfd-lazy-create to main.

Wasmtime GitHub notifications bot (Feb 03 2022 at 20:47):

cfallin updated PR #3760 from memfd-lazy-create to main.

Wasmtime GitHub notifications bot (Feb 03 2022 at 20:47):

cfallin submitted PR review.

Wasmtime GitHub notifications bot (Feb 03 2022 at 20:47):

cfallin created PR review comment:

Done!

Wasmtime GitHub notifications bot (Feb 03 2022 at 21:09):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Feb 03 2022 at 21:20):

cfallin merged PR #3760.

Last updated: Dec 23 2024 at 13:07 UTC