Re: DPDK and energy efficiency

[Etienne-Victor Depasquale <edepa () ieee org>]

I forgot to point out that on Friday 26th, I'll share the results collected
through a link or a series of screenshots.

Cheers,

Etienne

On Mon, Feb 22, 2021 at 2:15 PM Pawel Malachowski <
pawmal-nanog () freebsd lublin pl> wrote:

> Dnia Mon, Feb 22, 2021 at 01:01:45PM +0100, Etienne-Victor Depasquale
> napisał(a):
>
> > It is, after all, Intel's response to the problem of general-purpose
> > scheduling of its processors - which prevents the processor from being
> > viable under high networking loads.
>
> It totally makes sense to busy poll under high networking load.
> By high networking load I mean roughly > 7 Mpps RX+TX per one x86 CPU core.
>
> I partially agree it may be hard to mix DPDK and non-DPDK workload
> on a single CPU, not only because of advanced power management logic
> requirement for the dataplane application, but also due to LLC trashing.
> It heavily depends on usecase and dataset sizes, for example
> optimised FIB may fit nicely into cache and use only tiny, hot part
> of the dataset, but CGNAT Mflow mapping likely won't fit. For such
> a usecase I would recommand dedicated CPU or cache partitioning (CAT),
> if available.
>
> In case of low volume traffic like 20-40G of IMIX one can dedicate
> e.g. 2 cores and interleave busy polling with halt instructions to
> lower the usage significantly (~60-80% core underutilisation).
>
>
>
> --
> Pawel Malachowski
> @pawmal80


-- 
Ing. Etienne-Victor Depasquale
Assistant Lecturer
Department of Communications & Computer Engineering
Faculty of Information & Communication Technology
University of Malta
Web. https://www.um.edu.mt/profile/etiennedepasquale