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Io_uring, kTLS and Rust for zero syscall HTTPS server

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495 points guntars | 1 comments | 22 Aug 25 03:51 UTC | HN request time: 0s | source
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butterisgood ◴[22 Aug 25 15:00 UTC] No.44985475[source]▶
Where do people get the idea that one thread per core is correct on a system that deals with time slices?

In my experience “oversubscribing” threads to cores (more threads than cores) provides a wall-clock time benefit.

I think one thread per core would work better without preemptive scheduling.

But then we aren’t talking about Unix.

replies(4): >>44985631 #>>44986628 #>>44988220 #>>44988584 #
1. jandrewrogers ◴[22 Aug 25 16:38 UTC] No.44986628[source]▶
A mistake people make with thread-per-core (TPC) architecture is thinking you can pick and choose the parts you find convenient, when in reality it is much closer to "all or nothing". It may be worse to half-ass a TPC implementation than to not use TPC at all. However, TPC is more efficient in just about all contexts if you do it correctly.

Most developers are unfamiliar with the design idioms for TPC e.g. how to properly balance and shed load between cores.