Not enough CPU

Posted Nov 4, 2024 17:17 UTC (Mon) by shemminger (subscriber, #5739)
Parent article: The OpenWrt One system

The problem is that preventing bufferbloat requires more CPU than most SOHO routers have.
A typical Armv8 Cortex A53 can't run CAKE at 1G bit. It tops out at about 700Mbit for me.

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Not enough CPU

Posted Nov 5, 2024 2:18 UTC (Tue) by mtaht (guest, #11087) [Link] (4 responses)

I keep hoping to find a way to make cake's shaper multicore.

CAKE single-threaded?

Posted Nov 5, 2024 6:03 UTC (Tue) by DemiMarie (subscriber, #164188) [Link] (3 responses)

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

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.

Not enough CPU

Posted Nov 5, 2024 3:58 UTC (Tue) by jalla (guest, #101175) [Link] (1 responses)

It is a toy, unfortunately. pcengines had the same performance characteristics on the ancient jaguar platform, but with 3 m.2 slots. What a uniquely bizarre device in 2025. Mozilla made this mistake with boot2gecko only targetting beyond low end hardware.

If you're looking for something close to open, check-out odroid (which, is also ancient at this point on arm).

Not enough CPU

Posted Nov 6, 2024 8:01 UTC (Wed) by parametricpoly (subscriber, #143903) [Link]

Indeed. Banana Pi / Sinovoip people have a long history of making shit products. I think the earlier router routed all traffic without limitations while the router was booting. Not exactly secure. Also wtf is with providing images that don't work. This is something the Banana Pi makers have been doing all the time. While the community provides working open source images, they like to stick with binary BSP images that break the GPL.