Merged to api-next.

I think this patch is clean and we can do further improvements / tuning
later.

Regards,
Maxim.

On 22 June 2017 at 21:48, Honnappa Nagarahalli <
[email protected]> wrote:

> On 22 June 2017 at 10:30, Maxim Uvarov <[email protected]> wrote:
> > On 06/22/17 17:55, Brian Brooks wrote:
> >> On 06/22 10:27:01, Savolainen, Petri (Nokia - FI/Espoo) wrote:
> >>> I was asking to make sure that performance impact has been checked
> also when timers are not used, e.g. l2fwd performance before and after the
> change. It would be also appropriate to test impact in the worst case:
> l2fwd type application + a periodic 1sec timeout. Timer is on, but timeouts
> come very unfrequently (compared to packets).
> >>>
> >>> It seems that no performance tests were run, although the change
> affects performance of many applications (e.g. OFP has high packet rate
> with timers). Configuration options should be set with  defaults that are
> acceptable trade-off between packet processing performance and timeout
> accuracy.
> >>
> >> If timers are not used, the overhead is just checking a RO variable
> >> (post global init). If timers are used, CONFIG_ parameters have been
> >> provided. The defaults for these parameters came from the work to
> >> drastically reduce jitter of timer processing which is documented
> >> here [1] and presented at Linaro Connect here [2].
> >>
> >> If you speculate that these defaults might need to be changed, e.g.
> >> l2fwd, we welcome collaboration and data. But, this is not a blocking
> >> issue for this patch right now.
> >>
> >> [1] https://docs.google.com/document/d/1sY7rOxqCNu-
> bMqjBiT5_keAIohrX1ZW-eL0oGLAQ4OM/edit?usp=sharing
> >> [2] http://connect.linaro.org/resource/bud17/bud17-320/
> >>
> >
> > 1) we have all adjustable configs here
> > ./platform/linux-generic/include/odp_config_internal.h
> > that might be also needs to be there.
> >
> That file has all the global config values. These are internal to this
> timer implementation, hence they do not need to be moved.
> >
> > 2) Do we need something special in CI to check different config values?
>
> Nope.
> >
> > 3) Why it's compile time config values and not run time?
>
> These config values are particular to this timer implementation.
> Similar to config values in
> ./platform/linux-generic/include/odp_config_internal.h, these also
> will be compile time constants.
>
> >
> > Maxim.
> >
> >
> >>> -Petri
> >>>
> >>>
> >>> From: Maxim Uvarov [mailto:[email protected]]
> >>> Sent: Thursday, June 22, 2017 11:22 AM
> >>> To: Honnappa Nagarahalli <[email protected]>
> >>> Cc: Savolainen, Petri (Nokia - FI/Espoo) <[email protected]>;
> lng-odp-forward <[email protected]>
> >>> Subject: Re: [lng-odp] [API-NEXT PATCH v4] timer: allow timer
> processing to run on worker cores
> >>>
> >>> Petri, do you want to test performance before patch inclusion?
> >>> Maxim.
> >>>
> >>> On 21 June 2017 at 21:52, Honnappa Nagarahalli <mailto:
> [email protected]> wrote:
> >>> We have not run any performance application. In our Linaro connect
> >>> meeting, we presented numbers on how it improves the timer resolution.
> >>> At this point, there is enough configuration options to control the
> >>> effect of calling timer in the scheduler. For applications that do not
> >>> want to use the timer, there should not be any change. For
> >>> applications that use timers non-frequently, the check frequency can
> >>> be controlled via the provided configuration options.
> >>>
> >>> On 20 June 2017 at 02:34, Savolainen, Petri (Nokia - FI/Espoo)
> >>> <mailto:[email protected]> wrote:
> >>>> Do you have some performance numbers? E.g. how much this slows down
> an application which does not use timers (e.g. l2fwd), or an application
> that uses only few, non-frequent timeouts?
> >>>>
> >>>> Additionally, init.h/feature.h is not yet in api-next - so this would
> not build yet.
> >>>>
> >>>>
> >>>> -Petri
> >>>>
> >>>>
> >>>>> -----Original Message-----
> >>>>> From: lng-odp [mailto:mailto:[email protected]] On
> Behalf Of
> >>>>> Honnappa Nagarahalli
> >>>>> Sent: Tuesday, June 20, 2017 7:07 AM
> >>>>> To: Bill Fischofer <mailto:[email protected]>
> >>>>> Cc: lng-odp-forward <mailto:[email protected]>
> >>>>> Subject: Re: [lng-odp] [API-NEXT PATCH v4] timer: allow timer
> processing
> >>>>> to run on worker cores
> >>>>>
> >>>>> Are you saying we should be good to merge this now?
> >>>>>
> >>>>> On 19 June 2017 at 17:42, Bill Fischofer <mailto:
> [email protected]>
> >>>>> wrote:
> >>>>>> On Mon, Jun 19, 2017 at 4:19 PM, Honnappa Nagarahalli
> >>>>>> <mailto:[email protected]> wrote:
> >>>>>>> Hi Bill/Maxim,
> >>>>>>>      I do not see any further comments, can we merge this to
> api-next?
> >>>>>>>
> >>>>>>> Thanks,
> >>>>>>> Honnappa
> >>>>
> >>>>
> >>>
> >
>

Reply via email to