Starkast Wiki

jemalloc

https://github.com/jemalloc/jemalloc/wiki/Background

Links from 2025-10

• https://bsky.app/profile/nateberkopec.bsky.social/post/3lzyijqhu7d2y

Links from 2025-09

• Alternatives
  • https://github.com/microsoft/mimalloc
    • https://github.com/deadmanssnitch/buildpack-mimalloc
    • gaffneyc: "uses a bit more memory than jemalloc"
    • Numbers using https://github.com/SamSaffron/allocator_bench/
    • https://gist.github.com/gaffneyc/72ee723d43a76ca4edf79b791f1c41bf
  • tcmalloc
• https://jasone.github.io/2025/06/12/jemalloc-postmortem/ (maintainer goodbye)
  • https://news.ycombinator.com/item?id=44264958
  • new repo: https://github.com/facebook/jemalloc

Links from 2024-09

• Nate tweet: https://x.com/nateberkopec/status/1826390160113803353
• Heroku buildpack: https://github.com/gaffneyc/heroku-buildpack-jemalloc (the author is in Rails Perf Slack)
• jjb gist: https://gist.github.com/jjb/9ff0d3f622c8bbe904fe7a82e35152fc
• Nate: "5.3, no settings"
• Nate: "LD_PRELOAD for this image, and no, it doesn't matter. statically linking means you do get some goodies re: instrumentation but ofc that is not required."
• Trevor: "Note since Rails 7.2 jemalloc and yjit are both enabled by default (jemalloc via the Dockerfile template, which might be the best we can do without getting into Ruby Core) https://guides.rubyonrails.org/tuning_performance_for_deployment.html"