Re: DPDK and energy efficiency

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

> The way I saw, the questions induce the public to conclude that DPDK
> ALWAYS has 100% CPU usage, which is not true.


I don't concur.

Every research paper I've read indicates that, regardless of whether it has
packets to process or not, DPDK PMDs (poll-mode drivers) prevent the CPU
from falling into an LPI (low-power idle).

When it has no packets to process, the PMD runs the processor in a polling
loop that keeps utilization of the running core at 100%.

Cheers,

Etienne

On Mon, Feb 22, 2021 at 12:33 PM Douglas Fischer <fischerdouglas () gmail com>
wrote:

> I'm very happy to see interest in DPDK and power consumption.
>
> But IMHO, the questions do not cover the actual reality of DPDK.
> That característic of "100% CPU" depends on several aspects, like:
>  - How old are the hardware on DPDK.
>  - What type of DPDK Instructions are made(Very Dynamic as
> Statefull CGNAT, ou Static ACLs?)
>  - Using or not the measurements of DPDK Input/Drop/Fowarding.
>  - CPU Affinity done according to the demand of traffic
>  - SR-IOV (sharing resources) on DPDK.
>
> The way I saw, the questions induce the public to conclude that DPDK
> ALWAYS has 100% CPU usage, which is not true.
>
>
> Em seg., 22 de fev. de 2021 às 04:30, Etienne-Victor Depasquale <
> edepa () ieee org> escreveu:
>
> > Hello folks,
> >
> > I've just followed a thread regarding use of CGNAT and noted a suggestion
> > (regarding DANOS) that includes use of DPDK.
> >
> > As I'm interested in the breadth of adoption of DPDK, and as I'm a
> > researcher into energy and power efficiency, I'd love to hear your feedback
> > on your use of power consumption control by DPDK.
> >
> > I've drawn up a bare-bones, 2-question survey at this link:
> >
> > https://www.surveymonkey.com/r/J886DPY.
> >
> > Responses have been set to anonymous.
> >
> > Cheers,
> >
> > Etienne
> >
> > --
> > 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
>
>
> --
> Douglas Fernando Fischer
> Engº de Controle e Automação


-- 
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