From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-04-iad.dyndns.com (mxout-166-iad.mailhop.org [216.146.32.166]) by lists.bufferbloat.net (Postfix) with ESMTP id BE6F22E075B for ; Wed, 2 Feb 2011 11:17:05 -0800 (PST) Received: from scan-01-iad.mailhop.org (scan-01-iad.local [10.150.0.206]) by mail-04-iad.dyndns.com (Postfix) with ESMTP id 0653C83398E for ; Wed, 2 Feb 2011 19:17:06 +0000 (UTC) X-Spam-Score: 0.1 () X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 75.145.127.229 Received: from gw.co.teklibre.org (75-145-127-229-Colorado.hfc.comcastbusiness.net [75.145.127.229]) by mail-04-iad.dyndns.com (Postfix) with ESMTP id 5ED3F8338BC for ; Wed, 2 Feb 2011 19:17:01 +0000 (UTC) Received: from cruithne.co.teklibre.org (unknown [IPv6:2002:4b91:7fe5:2:21c:25ff:fe80:46f9]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "cruithne.co.teklibre.org", Issuer "CA Cert Signing Authority" (verified OK)) by gw.co.teklibre.org (Postfix) with ESMTPS id BCBE55E869 for ; Wed, 2 Feb 2011 12:16:59 -0700 (MST) Received: by cruithne.co.teklibre.org (Postfix, from userid 1000) id 1C9EF122145; Wed, 2 Feb 2011 12:16:59 -0700 (MST) From: d@taht.net (Dave =?utf-8?Q?T=C3=A4ht?=) To: "Richard Scheffenegger" Organization: Teklibre - http://www.teklibre.com References: <87bp2upinw.fsf@cruithne.co.teklibre.org> <877hdipfhf.fsf@cruithne.co.teklibre.org> <585FF290C0384319AA507AEF4BC8F3FB@srichardlxp2> Date: Wed, 02 Feb 2011 12:16:59 -0700 In-Reply-To: <585FF290C0384319AA507AEF4BC8F3FB@srichardlxp2> (Richard Scheffenegger's message of "Wed, 2 Feb 2011 19:37:07 +0100") Message-ID: <87y65ynt5g.fsf@cruithne.co.teklibre.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: bloat Subject: Re: [Bloat] TCP vegas vs TCP cubic 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: Wed, 02 Feb 2011 19:17:06 -0000 Thx. Wiki'd:=20 http://www.bufferbloat.net/projects/bloat/wiki/Windows_Tips Is there a windows equivalent of ethtool? "Richard Scheffenegger" writes: > For all the Windows Vista / Windows 7 Users around, they can enable > "Compound TCP", which is a Hybrid TCP Congestion Control approach: > > netsh int tcp set global congestionprovider=3Dctcp > > and, while you're at it, also enable ECN (lossless congestion control > feedback): > > netsh int tcp set global ecncapability=3Denabled > > If enough End Users enable ECN, core providers may be inclined to > deploy AQM with Packet Marking too... And as Home Gateways are those > which are prone to ECN implementation bugs, a full disconnect from the > internet (rather than certain sites not reachable) is quite easy to > diagnose at that end. > > Been running with ECN since a couple of months, and so far I have yet > to encounter a site that will consistently fail with ECN. Actually, > enabling ECN gives you more retries with the SYN (3x ECN+SYN, 3x > normal SYN), so in a heavy congested / bufferbloated environment, your > small flows might get through eventually, with higher probability. > > Regards, > Richard > > > > ----- Original Message -----=20 > From: "Dave "T=C3=A4ht"" > To: "Justin McCann" > Cc: "bloat" > Sent: Wednesday, February 02, 2011 5:29 PM > Subject: Re: [Bloat] TCP vegas vs TCP cubic > > >> >> Thx for the feedback. I've put up more information on the wiki at: >> >> http://www.bufferbloat.net/projects/bloat/wiki/Experiment_-_TCP_cubic_vs= _TCP_vegas >> >> (At least netnews had a "C"ancel message option. Wikis are safer to use >> before your first cup of coffee) >> >> Justin McCann writes: >> >>> On Wed, Feb 2, 2011 at 10:20 AM, Dave T=C3=A4ht wrote: >>>> Can I surmise that TCP cubic is like a dragster, able to go really fast >>>> in one direction down a straightaway, and TCP vegas more like an 80s >>>> model MR2, maneuverable, but underpowered? >>> >>> There are some parameters to tune, essentially setting the number of >>> packets you want queued in the network at any one time (see >>> http://neal.nu/uw/linux-vegas/). I haven't messed with it much myself, >>> but you might try to increase those just a bit -- if Vegas >> >> I am reading now. >> >>> underestimates the queue size and the queue empties, you'll never get >>> the throughput. Ideally there would always be exactly one packet in >>> the bottleneck queue. >> >> What a happy day that would be. >> >>> >>> But I think your results are pretty much expected with Vegas, since it >>> uses the increase in queuing latency as an early congestion indicator. >>> If everyone used it, we may be better off, but other congestion >>> algorithms aren't fair to Vegas since they wait until there are packet >>> drops to notice congestion. >> >> My thought was, is that if it were possible that the wireless side of a >> given stack used it, life might be better on that front. Ultimately. For >> people that upload stuff. >> >>>> On a failed hunch, I also re-ran the tests with a much larger >>>> congestion window: >>> I think you mean larger send/receive buffers instead of congestion >>> window? I'll bet the Vegas parameters are keeping the congestion >> >> Correction noted. Coffee needed. >> >>> window smaller than your send/receive buffer sizes, so they aren't >>> limiting you in the first place, so no improvement. >> >> I'll take a packet trace next time I run the test. >> >>> >>> The web100 patches (web100.org) are great for getting into the details >>> of how TCP is working. If you don't want to apply them yourself, you >>> can try the Live CD of perfSONAR-PS (http://psps.perfsonar.net/). It >>> might be useful to have an NDT >>> (http://www.internet2.edu/performance/ndt/) server running on your >>> home network, or use one at M-Lab. It doesn't need much resource-wise >>> but the web100 patches. >> >> Excellent suggestions. Building now. (It seems to want java and I don't >> think the little clients I have on this testbed can handle that well) >> >> At the moment my little testbed is fairly flexible and my queue of >> things to test is quite large. >> >> I have bloat-reducing patches for all the devices in the picture except >> for the laptop's , which is proving to be painful to look at. >> >> At the moment, I'd like to be getting, useful, interesting, >> *repeatable* results for a variety of well defined latency + throughput >> tests with... stock firmware and then be able to re-run the interesting >> series(s) against more custom configurations. >> >> I've only deployed the first patch on the wndr3700 thus far. It was >> *amazing*. >> >>> >>> Justin >> >> --=20 >> Dave Taht >> http://nex-6.taht.net >> _______________________________________________ >> Bloat mailing list >> Bloat@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/bloat >> > --=20 Dave Taht http://nex-6.taht.net