From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [RFC v2] fq_codel : interval servo on hosts Date: Tue, 04 Sep 2012 18:57:29 +0200 Message-ID: <1346777849.13121.50.camel@edumazet-glaptop> References: <1346396137.2586.301.camel@edumazet-glaptop> <1346421031.2591.34.camel@edumazet-glaptop> <1346421466.2591.38.camel@edumazet-glaptop> <1346503884.7996.65.camel@edumazet-glaptop> <1346772855.13121.40.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Tomas Hruby , Nandita Dukkipati , netdev , codel@lists.bufferbloat.net To: Dave Taht Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: codel-bounces@lists.bufferbloat.net Errors-To: codel-bounces@lists.bufferbloat.net List-Id: netdev.vger.kernel.org On Tue, 2012-09-04 at 09:40 -0700, Dave Taht wrote: > fq_codel has a standing queue problem, based on the fact that when a > queue empties, codel.h resets. This made sense for the single FIFO > codel but not multi-queued fq_codel. So after we hit X high rate > flows, target can never be achieved, even straining mightily, and we > end up with a standing queue again. > > Easily seen with like 150 bidirectional flows at 10 or 100Mbit. > > (as queues go, it's still pretty good queue. And: I've fiddled with > various means of draining multi-queue behavior thus far, and they > ended up unstable/unfair) No idea of what you mean by "codel.h resets". Please use small mails, one idea by mail.