How Discord Scaled Elixir to 5,000,000 Concurrent Users

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How Discord Scaled Elixir to 5,000,000 Concurrent Users

And some discussion on Hacker News about it (including some OTP 20.0 optimizations).

Their published libraries described in the blog post:

  • manifold: Fast batch message passing between nodes for Erlang/Elixir
  • ex_hash_ring: A fast consistent hash ring implementation in Elixir
  • fastglobal: Fast no copy globals for Elixir & Erlang
  • semaphore: Fast semaphore using ETS

At last the praised free book from Fred Hebert: Stuff Goes Bad: Erlang in Anger

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Nice :023:

I’ve made some changes to our Showcase section and moved this there :003:

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Oh now that is very cool, they made a lot of little micro-libraries (micro as in one-file) that are very useful and simple.

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Recompiling code on the fly so that the datastructure is “constant” is impossibly cool xD best cache ever

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Using Rust to Scale Elixir for 11 Million Concurrent Users

Nowadays it seems like they use a faster implementation with NIFs, here’s the library: SortedSet

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Thanks for the link, that is really handy. I implemented a custom MapSet with Erlang 21+ features which is 25% faster than the native MapSet, I expect this can be an even bigger improvement.

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You should submit a PR to Elixir then!

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Absolutely, I planned on submitting a PR after support for Erlang 20 was dropped. That will probably be quite a while though, so I’ll probably investigate conditional compilation instead.

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The top link has moved to How Discord Scaled Elixir to 5,000,000 Concurrent Users, and the update is at Using Rust to Scale Elixir for 11 Million Concurrent Users . Too bad that the original permalinks don’t redirect!

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