[wasm] mmap/lock free allocator optimizations #102265
Merged
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Right now on WASM we ask mmap for 16KB pages in the lock-free allocator, and mmap hands us 64KB pages that we end up wasting 3/4 of.
We also ask for zeroed pages, but we don't need zeroed pages because all of the lock-free allocator's callers memset or fully initialize their allocations anyway.
Partially fixes dotnet/perf-autofiling-issues#34303 and fixes dotnet/perf-autofiling-issues#34274