From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juliusz Chroboczek Subject: Re: [PATCH] Stochastic Fair Blue queue discipline Date: Tue, 08 Apr 2008 17:28:48 +0200 Message-ID: <7i7if8bc27.fsf@lanthane.pps.jussieu.fr> References: <87skxxb8br.fsf@pirx.pps.jussieu.fr> <47FAB688.7010807@trash.net> Mime-Version: 1.0 Content-Type: text/plain Cc: netdev@vger.kernel.org To: Patrick McHardy Return-path: Received: from shiva.jussieu.fr ([134.157.0.129]:58739 "EHLO shiva.jussieu.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752111AbYDHP4h (ORCPT ); Tue, 8 Apr 2008 11:56:37 -0400 In-Reply-To: <47FAB688.7010807@trash.net> (Patrick McHardy's message of "Tue\, 08 Apr 2008 02\:04\:24 +0200") Sender: netdev-owner@vger.kernel.org List-ID: > I experienced with SFB myself some time ago and recall > getting huge unfairness towards non-ECN connections. I've only done informal checking, but didn't test ECN against non-ECN. Will do, and I'll let you know the results. > I just found my old tree and it was just Blue, which might explain this Blue is supposed to be roughly fair w.r.t. TCP-compliant flows with similar RTT. If you see long-term unfairness with Blue at a single RTT, then something is wrong at the sender. I'll see if I can repeat your issues. Earlier versions of Linux did not reduce their sending rate when they received ECE and the congestion window was just 1 MSS. I don't know if this bug has been fixed. Juliusz