On Thu, 29 Nov 2018, Jonathan Morton wrote:
I'd say the important bits are only slightly harder than doing the same with fq_codel.
Ok, FQ_CODEL is way off to get implemented in HW. I haven't heard anyone even discussing it. Have you (or anyone else) heard differently?
I believe much of Cake's perceived CPU overhead is actually down to inefficiencies in the Linux network stack. Using a CPU and some modest auxiliary hardware dedicated to moving packets, not tied up in handling general-purpose duties, then achieving greater efficiency with reasonable hardware costs could be quite easy, without losing the flexibility to change algorithms later.
I need to watch the MT7621 packet accelerator talk at the most recent OpenWrt summit. I installed OpenWrt 18.06.1 on an Mikrotik RB750vGR3 and just clicked my way around in LUCI and enabled flow offload and b00m, it now did full gig NAT44 forwarding. It's implemented as a -j FLOWOFFLOAD iptables rule. The good thing here might be that we could throw unimportant high speed flows off to the accelerator and then just handle the time sensitive flows in CPU, and just make sure the CPU has preferential access to the media for its time-sensitive flow. That kind of approach might make FQ_CODEL deployable even on slow CPU platforms with accelerators because you would only run some flows through FQ_CODEL, where the bulk high-speed flows would be handed off to acceleration (and we guess they don't care about PDV and bufferbloat).
-- Mikael Abrahamsson email: swm...@swm.pp.se _______________________________________________ Bloat mailing list Bloat@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/bloat
