CAKE single-threaded?

Posted Nov 5, 2024 6:03 UTC (Tue) by DemiMarie (subscriber, #164188)
In reply to: Not enough CPU by mtaht
Parent article: The OpenWrt One system

Why is multicore shaping hard? Single-threaded shaping is definitely going to be more and more of a bottleneck.

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CAKE single-threaded?

Posted Nov 5, 2024 10:38 UTC (Tue) by Sesse (subscriber, #53779) [Link] (2 responses)

Fair queueing has, by definition, a lot of state. Anything involving large amounts of shared state is pretty hard to multithread efficiently.

CAKE single-threaded?

Posted Nov 5, 2024 15:43 UTC (Tue) by mtaht (guest, #11087) [Link] (1 responses)

I have been thinking about a shared timed token bucket, but really have got nowhere. Ideas over here: https://docs.google.com/document/d/1tTYBPeaRdCO9AGTGQCpoi...

If you are willing to give up pure fq and instead just try to schedule per core the complexity goes down.

CAKE single-threaded?

Posted Jan 19, 2025 4:59 UTC (Sun) by Simon80 (subscriber, #50887) [Link]

Would pipelining help make multicore more feasible for Cake? Specifically, instead of load balancing packets across cores, each packet would go through the same pipeline in order, with each stage executed on a different core. I don't know enough to guess whether that approach is applicable here, but if so, it would make it possible to keep processing every item in a single thread, and still benefit from multiple cores.