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Date: Wed, 4 Dec 2013 13:47:10 -0800
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From: Sambath Kumar Balasubramanian <sambath.balasubramanian@gmail.com>
To: Stephen Hemminger <stephen@networkplumber.org>
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Subject: Re: [dpdk-dev] Question on the Ring Library
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Thanks Stephen. I was going to do prototype something similar (not doing
the wakeup inline but using a background thread)
and is it a worthwhile effort to move this as a feature of the RTE ring or
is it best left at the application level.


On Wed, Dec 4, 2013 at 1:25 PM, Stephen Hemminger <
stephen@networkplumber.org> wrote:

> On Wed, 4 Dec 2013 03:46:36 -0800
> Sambath Kumar Balasubramanian <sambath.balasubramanian@gmail.com> wrote:
>
> > Hi,
> >
> >   The ring library seems to be an excellent IPC. But looking at one use
> > case where the fast path code posts events to event thread for example,
> the
> > event thread will spend some cycles polling the ring rather than waiting
> > for the event. One approach could be a fast path code basically posts the
> > event in the ring as is today and there is a background thread that polls
> > the queues and wakes up the event threads. This is similar to Linux
> > SOFTIRQs.The event threads are asynchronous. Is this a fair model to
> avoid
> > extra polling CPU cycles by the event threads? Is there any other
> > alternatives in dpdk?
> >
> > Regards,
> > Sambath
>
> I have in several cases combined RTE ring with use of eventfd + poll to
> get wakeup
>