cranelift

rust jit wasm webassembly runtime wasi cranelift sandbox wasmtime

Nick Fitzgerald e1f8b9b74b Wasmtime(pooling allocator): Batch decommits (#8590 ) This introduces a `DecommitQueue` for batching decommits together in the pooling allocator: * Deallocating a memory/table/stack enqueues their associated regions of memory for decommit; it no longer immediately returns the associated slot to the pool's free list. If the queue's length has reached the configured batch size, then we flush the queue by running all the decommits, and finally returning the memory/table/stack slots to their respective pools and free lists. * Additionally, if allocating a new memory/table/stack fails because the free list is empty (aka we've reached the max concurrently-allocated limit for this entity) then we fall back to a slow path before propagating the error. This slow path flushes the decommit queue and then retries allocation, hoping that the queue flush reclaimed slots and made them available for this fallback allocation attempt. This involved defining a new `PoolConcurrencyLimitError` to match on, which is also exposed in the public embedder API. It is also worth noting that we always use this new decommit queue now. To keep the existing behavior, where e.g. a memory's decommits happen immediately on deallocation, you can use a batch size of one. This effectively disables queueing, forcing all decommits to be flushed immediately. The default decommit batch size is one. This commit, with batch size of one, consistently gives me an increase on `wasmtime serve`'s requests-per-second versus its parent commit, as measured by `benches/wasmtime-serve-rps.sh`. I get ~39K RPS on this commit compared to ~35K RPS on the parent commit. This is quite puzzling to me. I was expecting no change, and hoping there wouldn't be a regression. I was not expecting a speed up. I cannot explain this result at this time. prtest:full Co-authored-by: Jamey Sharp <jsharp@fastly.com>		6 months ago
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src	Wasmtime(pooling allocator): Batch decommits (#8590)	6 months ago
Cargo.toml	Configure workspace lints, enable running some Clippy lints on CI (#7561)	12 months ago
LICENSE	Add license files	3 years ago
build.rs	Bump Wasmtime's MSRV to 1.76.0 (#8560)	6 months ago