From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-x22f.google.com (mail-wg0-x22f.google.com [IPv6:2a00:1450:400c:c00::22f]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 6518821F112 for ; Fri, 20 Dec 2013 13:58:47 -0800 (PST) Received: by mail-wg0-f47.google.com with SMTP id n12so3000246wgh.2 for ; Fri, 20 Dec 2013 13:58:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=5xiQkRrKEisEK2eVEjmlhRNDBVWVBY10E9ybdkN7wPw=; b=U6S1cE3ddh+AUTb2HO1+JAXmNKZNCEQY1cguaZh1GoObhbJoW23KjXDyytyFl9FVU7 ZE1HTLSkplzu5xoBr0M1N/lS0TzG2OxtXgTISlHgabBmLbQ4Pdk2qMymkihg9EUthiek ucFUjKBYpGjQcm6TM4DqIZRwOUTtptpEuuUxQalj85UBjlJarAHqz7/348g2YNu8UvtE p9fddMh49D9FbsXisfxGPV1sA0/kXoc+IID6Zt2LQJQ1ls8hblGEYfNHPBuFPQfOdCYh 5PMTGx8L9UTL8Fa56KF/pKJwO6A3tnii8MUnKP1A14263LjGnMmHBRvjrZ36fKlXy/u0 1JrQ== MIME-Version: 1.0 X-Received: by 10.180.90.230 with SMTP id bz6mr5542485wib.17.1387576725111; Fri, 20 Dec 2013 13:58:45 -0800 (PST) Received: by 10.217.123.69 with HTTP; Fri, 20 Dec 2013 13:58:45 -0800 (PST) In-Reply-To: <1387574550.00762811@apps.rackspace.com> References: <1D691810-3DD1-4899-9F63-E1713BD01840@gmail.com> <1387574550.00762811@apps.rackspace.com> Date: Fri, 20 Dec 2013 13:58:45 -0800 Message-ID: From: Dave Taht To: David Reed Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Cc: "cerowrt-devel@lists.bufferbloat.net" Subject: Re: [Cerowrt-devel] Anything but "AQM" X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Dec 2013 21:58:48 -0000 On Fri, Dec 20, 2013 at 1:22 PM, wrote: > Given that there is no likelihood of making localized queue management > "intelligent" because it has no global information whatsoever, I strongly > suggest that "smart" "intelligent" and even "active" are hugely misleadin= g. > > > > They are based on a completely false premise - that queues should be allo= wed > to build at all, and that local information can solve highly transient > global problems. > David, I think we should have this discussion offline. I thought you were p= aying attention on the bloat list. > "Dumb Queue Management" is going to be far superior. Keep the queue at z= ero > length, and try to be fair. Heh. > There's a simple way to do the latter - use a filter (similar to a Bloom > filter) that captures recent/frequent users of the queue, and when the qu= eue Tried SFB. It didn't work. > on an outbound link grows more than about 2-3 packets (double buffering i= s > all you need to keep the link full) discard the most recent and frequent > packets (or send information that tells them to slow down). Nope, due to the bursty nature of tcp and of things like wifi packet aggregation you need be able to absorbe a burst of an RTT's worth of queue around, what kathy and van call "good queue". I have a lot of hope that now that we are seeing "paced" tcp schedulers that we'll see much less structure at the bottlenecks from isochronous sources, but the batchy ones like gpon, wifi, and cable, will induce more, and structure does seem to arrive from navigating bottlenecks also, as per slide 30 in this: http://www.pollere.net/Pdfdocs/QrantJul06.pdf > > > > There's been a lot of wasted time and effort trying to build queues long > enough so that you can be "intelligent", but by then you have already los= t > the battle. You've gotten into a positive feedback loop where you have > encouraged the endpoints to send more packets than you can ever drain out= of > the queue. The goal here is 100% utilization at 0 latency. We are getting preciously close to it with fq_codel and derivatives. > I truly, truly do not understand why people don't look at realistic netwo= rk > loads and structures. I like to think I do. > > > > > > On Friday, December 20, 2013 3:52pm, "Rich Brown" > said: > >> Dave, >> >> You wrote: >> >> > What's in a name? AQM has been pretty thoroughly defined to equal >> > active queue *length* management and not packet scheduling. >> > Overloading "AQM" what cerowrt does is apt to cause even more >> > confusion in the field than it already does. We discussed using LBO as >> > a word but that appears hopelessly overloaded with leveraged buy out. >> > >> > I go back to one I liked a while back: >> > >> > Smart Queue Management. (SQM) >> > >> > This got dissed on the aqm list too, but so far a viable alternative >> > TLA has not appeared. It's sufficiently different to hang a different >> > definition off of ("Smart queue management is an intelligent >> > combination of better packet scheduling (flow queuing) techniques >> > along with with active queue length management (aqm)=94) >> >> and >> >> > Any ideas for a name for packet scheduling, prioritization, and active >> > queue management better than just "AQM", or "QoS"? >> > >> > SQM "Smarter Queue Management" >> > CeroShaper >> > LBO Latency and Bandwidth Optimisation >> >> I was prepared to agree with =93SQM=94, and had written a long note >> (below) when my brain uttered =93Intelligent Queue Management=94. >> I=92m not convinced that one is better than the other=85 >> >> Rich >> >> =3D=3D=3D=3D=3D The benefits of SQM =3D=3D=3D=3D=3D=3D >> >> Wikipedia sez=85 SQM may refer to: >> >> - Sociedad Qu=EDmica y Minera de Chile - a Chilean mining and chemical >> enterprise >> - Software quality management >> - Spectrum quality management >> - Supplier Quality Management >> - Sensors Quality Management Inc. - provides unbiased evaluations of a >> company's >> operations relating to issues of quality, service, cleanliness and value >> - Sky Quality Meter, a device for measuring light pollution >> >> and also : S=E3o Miguel do Araguaia airport IATA code >> >> sqm may refer to : >> >> - square metre >> - Windows Live Messenger log file extension >> >> So it doesn=92t appear that there are any seriously conflicting uses of = that >> TLA=85 >> >> And I prefer =93Smart Queue Management=94 to =93Smarter Queue >> Management=94. We=92ll leave to someone else to go out on the weak branc= h >> and espouse =93Smarter queue management=94 and =93Smartest queue >> management=94. (What comes after that? =93Smart and a half=94, >> Smart**2"?) >> >> Rich >> _______________________________________________ >> Cerowrt-devel mailing list >> Cerowrt-devel@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/cerowrt-devel >> --=20 Dave T=E4ht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.= html