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Concurrency in Haskell: Fast, Simple, Correct

(bitbashing.io)
193 points ingve | 1 comments | 14 Apr 25 10:47 UTC | HN request time: 0.204s | source
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michalsustr ◴[17 Apr 25 05:51 UTC] No.43713518[source]▶
I’m not familiar with Haskell concurrency. The combination of green threads and large memory allocations due to immutable data structures sounds like it would be hard to implement a web server handling 10k+ concurrent requests on commodity hardware?

Btw. too bad author talks about microsecond guarantees usage but does not provide a link, that would be interesting reading.

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1. _jackdk_ ◴[17 Apr 25 10:50 UTC] No.43715073[source]▶
The interaction of laziness and purity means that the memory costs are not always what you think. Purity means that it's a lot safer to share structure between old and new versions of a data structure where an imperative language would have to do defensive copying, and laziness means that you can incrementally amortise the cost of expensive rebalancing operations (Okasaki is the standard reference for this).