Re: [dpdk-dev] meter: excess token bucket update in srtcm

[Nikhil Jagtap <nikhil.jagtap@gmail.com>]

Hi Cristian,

Thanks for the confirmation. I have submitted a patch for the same.
http://dpdk.org/ml/archives/dev/2016-September/046226.html

Regards,
Nikhil

On 6 September 2016 at 15:26, Dumitrescu, Cristian <
cristian.dumitrescu@intel.com> wrote:

> Hi Nikhil,
>
> It also looks to me that you are right. Sorry, my mistake when translating
> the RFC into code.
>
> Challenge in fixing this is how to code it using minimal number of
> branches ...
>
> Thanks,
> Cristian
>
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Nikhil Jagtap
> > Sent: Tuesday, September 6, 2016 7:30 AM
> > To: Ramia, Kannan Babu <kannan.babu.ramia@intel.com>
> > Cc: dev@dpdk.org
> > Subject: Re: [dpdk-dev] meter: excess token bucket update in srtcm
> >
> > Hi Kannan,
> >
> > Thank you for your reply. I will submit the patch on similar lines I had
> > used for my test.
> >
> > Regards,
> > Nikhil
> >
> > On 6 September 2016 at 10:40, Ramia, Kannan Babu <
> > kannan.babu.ramia@intel.com> wrote:
> >
> > > Hi Nikhil
> > >
> > > You could submit a patch, something like that below logic
> > >
> > > If( ((n_periods * m->cir_bytes_per_period) > (m->cbs-m->tc))
> > >         te = m->te + ((n_periods * m->cir_bytes_per_period) -
> > > (m->cbs-m->tc));
> > >
> > > and this should be done before m->tc update.
> > >
> > >
> > > Regards
> > > Kannan Babu
> > >
> > > -----Original Message-----
> > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Nikhil Jagtap
> > > Sent: Tuesday, September 6, 2016 9:43 AM
> > > To: Dumitrescu, Cristian <cristian.dumitrescu@intel.com>
> > > Cc: dev@dpdk.org
> > > Subject: Re: [dpdk-dev] meter: excess token bucket update in srtcm
> > >
> > > Hi,
> > > Can someone please comment on this?
> > >
> > > Nikhil
> > >
> > > On 31 August 2016 at 15:32, Nikhil Jagtap <nikhil.jagtap@gmail.com>
> wrote:
> > >
> > > > Hi,
> > > >
> > > > As per srTCM RFC 2697, we should be updating the E bucket only after
> > > > the C bucket overflows.
> > > > "Thereafter, the token counts Tc and Te are updated CIR times per
> > > > second as follows:
> > > >      o If Tc is less than CBS, Tc is incremented by one, else
> > > >      o if Te is less then EBS, Te is incremented by one, else
> > > >      o neither Tc nor Te is incremented."
> > > >
> > > > However in the current DPDK implementation of srTCM, we are updating
> > > > both the buckets simultaneously at the same rate (CIR). This will
> > > > result in a token accumulation rate of (2*CIR). This seems like a bug
> > > > to me. Can you confirm this?
> > > >
> > > > Nikhil
> > > >
> > > >
> > >
>