[aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-07-20 Thread Roland Bless
Dear All, we (Polina and I) have two questions concerning the behavior of the `count` variable in Codel which can be summarized as: 1. after exiting dropping state, count is usually reset, unless "the next drop state is entered too close to the previous one". This special case is not explained in

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-07-20 Thread Agarwal, Anil
/2015-June/001023.html I have attached the updated document. Regards, Anil -Original Message- From: aqm [mailto:aqm-boun...@ietf.org] On Behalf Of Roland Bless Sent: Monday, July 20, 2015 12:49 PM To: aqm@ietf.org Subject: [aqm] Codel's count variable and re-entering dropping sta

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-07-20 Thread Jonathan Morton
I can’t speak for Kathy, but as Cake’s author I have some insight into the changes I’ve made to the associated version of Codel. > Ronald Bless: > 1. after exiting dropping state, count is usually reset, unless "the > next drop state is entered too close to the previous one”. In fact, in most c

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-08-14 Thread Polina Goltsman
Dear Jonathan, Thanks for your extensive answer. If you could comment on a couple more things: 1. in Cake, count saturates at 2^32-1, am I right (https://github.com/dtaht/sch_cake/blob/master/codel5.h#L352). could it make sense to saturate count when interval/sqrt(count) and interval/sqrt(

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-08-14 Thread Jonathan Morton
> 1. in Cake, count saturates at 2^32-1, am I right > (https://github.com/dtaht/sch_cake/blob/master/codel5.h#L352). > > could it make sense to saturate count when interval/sqrt(count) and > interval/sqrt(count+1) are indistinguishable in timer resolution? Actually it saturates at 2^16-1, since

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-08-14 Thread Polina Goltsman
first, thanks again... I forgot one thing though: What is the default value of "threshold" for default interval and target? -- Best Regards On 08/14/2015 04:52 PM, Jonathan Morton wrote: 1. in Cake, count saturates at 2^32-1, am I right (https://github.com/dtaht/sch_cake/blob/master/codel5.h

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-08-14 Thread Jonathan Morton
> On 14 Aug, 2015, at 18:25, Polina Goltsman > wrote: > > What is the default value of "threshold" for default interval and target? >From sch_cake.c 694-696: fqcd->cparams.target = max(byte_target_ns, ns_target); fqcd->cparams.interval = max(MS2TIME(100) + fqcd->cparams.target

Re: [aqm] Codel's count variable and re-entering dropping state at small time intervals

2015-08-14 Thread Jonathan Morton
> On 14 Aug, 2015, at 16:10, Polina Goltsman > wrote: > > My question is - are these changes valid for a standalone Codel or are they > specifically made to optimize Cake's scheduler? Incidentally, if you want to test this version of Codel standalone, you can do so within Cake, by turning of