Wasmtime GitHub notifications bot (Feb 16 2022 at 22:25): Wasmtime GitHub notifications bot (Feb 16 2022 at 22:25):alexcrichton opened PR #3819 from less-memory-on-compile to main:
Previously memfd-based image construction had a hard limit of a 1GB
memory image but this mean that tiny wasm modules could allocate up to
1GB of memory which became a bit excessive especially in terms of memory
usage during fuzzing. To fix this the conversion to a static memory
image has been updated to first do a conversion to paged memory
initialization, which is sparse, followed by a second conversion to
static memory initialization.The sparse construction for the paged step should make it such that the
upper/lower bounds of the initialization image are easily computed, and
then afterwards this limit can be checked against some heuristics to
determine if we're willing to commit to building up a whole static image
for that module. The heuristics have been tweaked from "must be less
than 1GB" to one of two conditions must be true:
Either the total memory image size is at most twice the size of the
original paged data itself.Otherwise the memory image size must be smaller than a reasonable
threshold, currently 1MB.We'll likely need to tweak this over time and it's still possible to
cause a lot of extra memory consumption, but for now this should be
enough to appease the fuzzers.Closes #3815
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Wasmtime GitHub notifications bot (Feb 16 2022 at 23:08):cfallin submitted PR review.
Wasmtime GitHub notifications bot (Feb 16 2022 at 23:08):cfallin submitted PR review.
Wasmtime GitHub notifications bot (Feb 16 2022 at 23:08):cfallin created PR review comment:
Constant for this?
Wasmtime GitHub notifications bot (Feb 16 2022 at 23:08):cfallin created PR review comment:
s/theortetically/theoretically/
Wasmtime GitHub notifications bot (Feb 17 2022 at 15:33):alexcrichton updated PR #3819 from less-memory-on-compile to main.
Wasmtime GitHub notifications bot (Feb 17 2022 at 16:37):alexcrichton merged PR #3819.
Last updated: Dec 23 2024 at 12:05 UTC