jemalloc/jemalloc

Health v2 · maintenance only

Flags: no_license

Adoption not part of the score

11065 stars · 1638 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

jemalloc is a general-purpose malloc(3) memory allocator implementation emphasizing fragmentation avoidance and scalable concurrency support. It originated as the FreeBSD libc allocator and includes developer features such as heap profiling and extensive monitoring and tuning hooks.

Use cases

• reduce memory fragmentation in long-running server applications
• replace the system malloc for better multi-threaded allocation performance
• profile heap usage and debug memory issues in C/C++ programs
• tune allocator behavior for demanding applications
• use as the system allocator on FreeBSD

When to choose

• your application suffers from heap fragmentation or allocator contention under high concurrency
• you need heap profiling and introspection hooks
• you want a battle-tested allocator with predictable behavior

When to avoid

• you need a simple allocator for a small single-threaded program where the system malloc suffices
• you want a modern allocator with a different feature set like mimalloc or snmalloc

Facets

library · maturity stable

developer-tools monitoring developer-tools performance operating-systems bsd cpp c cross-platform memory-allocator malloc heap-profiling fragmentation concurrency performance linux macos

Member repositories

For agents

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