From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailout-de.gmx.net (mailout-de.gmx.net [213.165.64.23]) by huchra.bufferbloat.net (Postfix) with SMTP id B30BA21F0FF for ; Sat, 4 Aug 2012 06:38:56 -0700 (PDT) Received: (qmail invoked by alias); 04 Aug 2012 13:38:53 -0000 Received: from unknown (EHLO srichardlxp2) [213.143.107.142] by mail.gmx.net (mp001) with SMTP; 04 Aug 2012 15:38:53 +0200 X-Authenticated: #20720068 X-Provags-ID: V01U2FsdGVkX18zbFoEcAQzuMVyPgjyqZctt3UMp2M3q+cyXUn45P ieOv44D6ZKd0Ew Message-ID: From: "Richard Scheffenegger" To: =?iso-8859-1?Q?Roger_J=F8rgensen?= , =?iso-8859-1?Q?Dave_T=E4ht?= , "Bob Briscoe" References: <1344048299-26267-1-git-send-email-dave.taht@bufferbloat.net> Date: Sat, 4 Aug 2012 15:38:48 +0200 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 X-Y-GMX-Trusted: 0 Cc: codel@lists.bufferbloat.net Subject: Re: [Codel] [RFC PATCH] codel: ecn mark at target X-BeenThere: codel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: CoDel AQM discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Aug 2012 13:38:58 -0000 Hi, My 0.02 EUR: mark every packet with a sojourn time above target is OK. The reaction of the congestion controller to ECN marks need to be more differentiated; ECN can deliver much more fine-grained information about the current state of the network. If a congestion controller (e.g. legacy 3168 ECN TCP) chooses to overshoot in it's reaction, thats a problem for that particular controller... But even if every packet of a window is marked, a legacy TCP will only reduce cwnd once per window, reacting the same as is a non-ECN had a single drop in that window... DCTCP (ECN alpha/beta) does things more fine-grained, and would push legacy (non ECN) out of the way, while maintainig full bandwidth and very low sojourn time (queue occupancy). Fixing the reaction of congestion controllers to ECN signals (deliberate plural) will be the next step in that area... Best regards, Richard ----- Original Message ----- From: "Roger Jørgensen" To: "Dave Täht" Cc: Sent: Saturday, August 04, 2012 9:00 AM Subject: Re: [Codel] [RFC PATCH] codel: ecn mark at target On Sat, Aug 4, 2012 at 4:44 AM, Dave Täht wrote: > From: Dave Taht > > The consensus at ietf was that ecn marking should start at > target, and then the results fed into the codel drop scheduler. > > While I agree with the latter, I feel that waiting an interval > before starting to mark will be more in-tune with the concept > of a sojourn time, and lead to better utilization. > > As I am outnumbered and outgunned, do it at target. Well, what do you think is The Best way of doing it? Prove'em wrong if you really think they are wrong;) -- Roger Jorgensen | ROJO9-RIPE rogerj@gmail.com | - IPv6 is The Key! http://www.jorgensen.no | roger@jorgensen.no _______________________________________________ Codel mailing list Codel@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/codel