On 22 June 2017 at 10:30, Maxim Uvarov <maxim.uva...@linaro.org> 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:maxim.uva...@linaro.org] >>> Sent: Thursday, June 22, 2017 11:22 AM >>> To: Honnappa Nagarahalli <honnappa.nagaraha...@linaro.org> >>> Cc: Savolainen, Petri (Nokia - FI/Espoo) <petri.savolai...@nokia.com>; >>> lng-odp-forward <lng-odp@lists.linaro.org> >>> 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:honnappa.nagaraha...@linaro.org> 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:petri.savolai...@nokia.com> 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:lng-odp-boun...@lists.linaro.org] On Behalf >>>>> Of >>>>> Honnappa Nagarahalli >>>>> Sent: Tuesday, June 20, 2017 7:07 AM >>>>> To: Bill Fischofer <mailto:bill.fischo...@linaro.org> >>>>> Cc: lng-odp-forward <mailto:lng-odp@lists.linaro.org> >>>>> 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:bill.fischo...@linaro.org> >>>>> wrote: >>>>>> On Mon, Jun 19, 2017 at 4:19 PM, Honnappa Nagarahalli >>>>>> <mailto:honnappa.nagaraha...@linaro.org> wrote: >>>>>>> Hi Bill/Maxim, >>>>>>> I do not see any further comments, can we merge this to api-next? >>>>>>> >>>>>>> Thanks, >>>>>>> Honnappa >>>> >>>> >>> >
