A new draft has been posted to address this issue. Thanks,
Rong On 4/13/16, 5:17 AM, "aqm on behalf of Rasool Al-Saadi" <aqm-boun...@ietf.org on behalf of ralsa...@swin.edu.au> wrote: > >On Tuesday, 5 April 2016, Rong Pan (ropan) wrote: >> >> Rasool, >> >> Thanks for your detailed review. Please see the comments below and a new >> draft has been posted. >> >> Regards, >> >> Rong >> >> >For new drop_prob calculation, how can drop_prob_ be just a division of >> >queue lengths? >> > drop_prob_(i)=queue_.byte_length(i)/max(queue_.byte_length(i)) >> >> >> >>>>>>>>>>>>>>>>>>>>>>>>>RP: Let¹s say there are two flows that are >> >>>>>>>>>>>>>>>>>>>>>>>>>queued into >> two sfq queues. One flow is an elephant flow and one flow is mice flow. >>Total >> latency is caused by the elephant flow. The above equation makes sure >>that >> the mice flow (whose queue length is zero, or very small amount) won¹t >>be >> dropped. >> Besides, since it is mice flow, it would be hard to measure its >>departure rate >> as the queue would never build up.qdelay >> > >Thank you for the explanation. I found section 4.6 SFQ-PIE in [*] is >clearer than in the draft. I hope SFQ paragraph of PIE draft becomes a >little clearer. >[*] >http://www.cablelabs.com/wp-content/uploads/2014/06/DOCSIS-AQM_May2014.pdf > >> > >> >5) In pages 23 and 24, >> > >> >> //If the queue has been idle for a while, turn off PIE >> >> //reset counters when accessing the queue after some idle >> >> //period if PIE was active before >> >> if ( PIE->drop_prob_ == 0 && PIE->qdelay_old_ == 0 >> >> && queue_.byte_length() == 0) { >> >> PIE->active_ = INACTIVE; >> > >> >According to section 5.3 (Turning PIE on and off), the condition of >> >deactivating PIE should be: >> > >> >if (PIE->drop_prob_ == 0 and current_qdelay < QDELAY_REF/2 and >> > PIE->qdelay_old_ < QDELAY_REF/2) { >> >> >> >>>>>>>>>>>>>>>>>>>>>>>>>>RP: Fixed. >> > >I am unsure whether section 5.3 is correct or the old code (in >draft-ietf-aqm-pie-05.txt) with queue_.byte_length() == 0 was correct. In >my PIE implementation, I found that without using queue_.byte_length() == >0, PIE turns off after a very short period and causes queue delay to >become uncontrolled until queue length exceeds 1/3 drop-tail size. I put >queue_.byte_length() == 0 condition and I got better results. > >Regards, >Rasool > >_______________________________________________ >aqm mailing list >aqm@ietf.org >https://www.ietf.org/mailman/listinfo/aqm _______________________________________________ aqm mailing list aqm@ietf.org https://www.ietf.org/mailman/listinfo/aqm
