Use jemalloc as global allocator on Linux#179
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rocketman-code merged 1 commit intomainfrom Feb 27, 2026
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musl's allocator makes 3,200+ mmap/munmap/brk syscalls for chainsaw's workload (~64 allocs/file, 85% <= 64 bytes). jemalloc services the same workload with 23 syscalls. A/B on Linux VPS (wrangler cold, 3447 modules): 531ms -> 329ms (1.61x). macOS is neutral (libmalloc is already magazine-based). Uses target-conditional dep so macOS never compiles jemalloc. Closes #178
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Summary
tikv-jemallocatoras a Linux-only dependency via target-conditional[target.'cfg(target_os = "linux")'.dependencies]#[cfg(target_os = "linux")])Benchmark
A/B on Linux VPS (wrangler cold, 3447 modules,
--no-cache):1.61x faster. System time halved — musl's allocator makes 3,200+ mmap/munmap/brk syscalls for chainsaw's workload; jemalloc services the same with 23.
macOS is neutral (libmalloc is already magazine-based).
Test plan
cargo test --workspacepasses (274 tests)cargo clippy --workspace --all-targets -- -D warningscleanCloses #178