> -----Original Message----- > From: Thomas Monjalon <[email protected]> > Sent: Thursday, March 31, 2022 8:39 PM > To: satish amara <[email protected]> > Cc: [email protected]; Singh, Jasvinder <[email protected]>; > Dumitrescu, Cristian <[email protected]> > Subject: Re: Fwd: QOS sample example. > > +Cc QoS scheduler maintainers (see file MAINTAINERS) > > 31/03/2022 18:59, satish amara: > > Hi, > > I am trying to understand the QOS sample scheduler application code. > > Trying to understand what is tc_period in the config. > > 30. QoS Scheduler Sample Application — Data Plane Development Kit > > 21.05.0 documentation (dpdk.org) > > <https://doc.dpdk.org/guides- > 21.05/sample_app_ug/qos_scheduler.html> > > Is tc_period same as tb_period tb_period Bytes Time period that > > should elapse since the last credit update in order for the bucket to > > be awarded tb_credits_per_period worth or credits. > > Regards, > > Satish Amara > >
tc_period and tb_period are different. TC period is related to pipe tc rate limiting mechanism while tb period relates to traffic shaping mechanism (token bucket) implemented at pipe level. tc_period represents the time interval to compute pipe TC credits (bytes). In each interval (tc_period value), credits are initialised to a fixed value. It is configurable parameter and should be carefully selected to avoid deadlock situation which arises when number of pipe TC credits (computed using tc_period) is smaller than the MTU. Please refer https://doc.dpdk.org/guides/prog_guide/qos_framework.html for more details.
