perf: add jemalloc as default allocator - #47
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reduces allocation contention under multi-threaded workloads. profiling showed ~7.7% CPU time spent in malloc/cfree with system allocator. jemalloc uses per-thread caches to minimize contention. enabled by default via feature flag. can be disabled with --no-default-features for platforms that don't support jemalloc.
kacy
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Feb 11, 2026
perf: add jemalloc as default allocator
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summary
adds jemalloc as the default memory allocator for ember-server. reduces allocation contention under multi-threaded workloads.
benchmarks (GCP c2-standard-8)
profiling showed ~7.7% CPU time in malloc/cfree with system allocator. jemalloc's per-thread caches reduce this contention.
changes
tikv-jemallocatoras optional dependency (enabled by default)--no-default-featuresdisables jemalloc for platforms that don't support ittest plan
--no-default-featuresdesign notes
the multi-core scaling issue persists (8 shards ≈ 1 shard performance). jemalloc addresses allocation contention but the main bottleneck is channel overhead (futex operations) from cross-thread request routing. addressing that requires architectural changes (connection affinity or sharded acceptors).