Re: HTB accuracy for high speed
From: Jarek Poplawski <hidden>
Date: 2009-05-19 11:03:19
On Tue, May 19, 2009 at 02:27:47AM +0300, Vladimir Ivashchenko wrote:
quoted
With bond + HFSC + sfq, I'm able to reach the speed. It doesn't seem to overspill with 580 mbps load. Jarek, would your patches help with HSFC overspill ? I will check tomorrow under 750 mbps load.
The gen_estimator patch should fix only the effect of rising rate after flow stop, and maybe similar overflows while reporting rates around 1Gbit. It would show on tc stats of HFSC or HTB, but doesn't affect actual scheduling rates. The iproute2 tc_core patch can matter for HTB scheduling rates if there are a lot of small packets (e.g. 100 byte for rate 500Mbit) possibly mixed with bigger ones. It doesn't matter for HFSC or rates <100Mbit.
Please disregard my comment about HFSC. It still overspills heavily. On a 400 mbps limit, I'm getting 520 mbps actual throughput.
I guess you should send some logs. Your previous report seem to show the sum of sc rates of of children could be too high. You seem to expect the parent's sc and ul should limit this, but actually children rates decide and parent's rates are mainly for lending/borrowing (at least in HTB). So, it would be nice to try with one leaf class first, (similarly to Antonio) how high rates are respected. High drop should be OK if the flow is much faster than scheduling/ hardware send rate. It could be a bit higher than in older kernels because of limited requeuing, but this could be corrected with longer queue lenghts (sfq has a very short queue: max 127). Jarek P.