From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from uplift.swm.pp.se (ipv6.swm.pp.se [IPv6:2a00:801::f]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by huchra.bufferbloat.net (Postfix) with ESMTPS id DD4C921F1CC for ; Thu, 21 Mar 2013 12:25:38 -0700 (PDT) Received: by uplift.swm.pp.se (Postfix, from userid 501) id 6ACCD9C; Thu, 21 Mar 2013 20:25:35 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by uplift.swm.pp.se (Postfix) with ESMTP id 5DA8C9A; Thu, 21 Mar 2013 20:25:35 +0100 (CET) Date: Thu, 21 Mar 2013 20:25:35 +0100 (CET) From: Mikael Abrahamsson To: Oliver Hohlfeld In-Reply-To: <514B5AC8.8000502@net.t-labs.tu-berlin.de> Message-ID: References: <51408BF4.7090304@cisco.com> <514B5AC8.8000502@net.t-labs.tu-berlin.de> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) Organization: People's Front Against WWW MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: tsvwg@ietf.org, bloat Subject: Re: [Bloat] [tsvwg] how much of a problem is buffer bloat today? X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Mar 2013 19:25:39 -0000 On Thu, 21 Mar 2013, Oliver Hohlfeld wrote: > In summary, the question on how much of a problem buffer bloat currently > is cannot be fully answered and still requires further research. Buffer bloat is a problem on basically all access forms apart from ETTH. Usually ETTH is produced using L2 or L3 switches with very small buffers (5 ms or so), and policing is used instead of buffering for limiting service rate. This means high speed TCP flows will sawtooth their performance over time because of large amount of consecutive drops, meaning low bw interactive flows are less impacted. So it's my belief that your measurements means most people don't actually put congestion pressure on their accesses, thus the large buffers are seldom used and you're not seeing buffering. -- Mikael Abrahamsson email: swmike@swm.pp.se