From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-x233.google.com (mail-qk0-x233.google.com [IPv6:2607:f8b0:400d:c09::233]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 6365B3B25E for ; Sat, 15 Oct 2016 00:39:28 -0400 (EDT) Received: by mail-qk0-x233.google.com with SMTP id f128so164809190qkb.1 for ; Fri, 14 Oct 2016 21:39:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=T3ScbVhpIFv8SyVSOYv2jKQeX3I99EtzIm10uLmMSHI=; b=qUHEYL2aKEAz/WxcZabfUTKCOid4GZV9tRE33vdlF/JXcRPSPtiK8y3D5LQOott/j0 Icnw3hAlyC7lT43dfB7nilHyeNIHX20HjomgZTsmvlxaj7n3s1shprUN6X2tpERzHTTi gxKFAYSGehCiPrML4bo20s81qk9jSoPFhywKIstsiYCa0aLq1NyxUzYsyTCb5OksAyhO 0Pyz5ilg0VAJmkq3WvJS6h35rNbANoCVy3/DRlE4QDQtY9RroFzi8qhjRk/6dYb6LHqp +/vM2qKrWBL3kTe4wPYll3LPGPra/ttcySYjHS5n80twm51tKjTzqGguV4mTdHkdd27Z IbWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=T3ScbVhpIFv8SyVSOYv2jKQeX3I99EtzIm10uLmMSHI=; b=BnOuPJNY0v2PzqJHpVsz2nnXTDk79vw1xmYpc6JIQaoulJ26m5jRvDDZ5TfVcRlBvt 64xbX5xlmL3hUI7NMMIMwa/jW5/g70S4rwimH2PvfKfGHoiCw4TogBo8GB4wrp2/cYAU GT3dtDnDUqENfC+MucfTLyzUW7J19xXc5Bt6Y5bl40XyTuIGLwnd8vEBf0h/cSUQ555V r7BPPi2aVTS6HPmRW6kiPVBkSFCqwlA9t5RNUv95ljut7S19aaT437PI5SxBYFam11Do OsKBNpvS47CWAl+TzrzpgmxDALfQvYbW3HBIYE9GNzb+bzE+zWkppDUccvxLUp26JDIC ftzw== X-Gm-Message-State: AA6/9RkEgIdivO7e7/MizIhAuNobdV8LJ/N48pLYcHkA+aXGQ9ng01pOqrVLwQgRA0MSOu9SALetsPCunnZGCA== X-Received: by 10.55.215.87 with SMTP id m84mr16796326qki.196.1476506367874; Fri, 14 Oct 2016 21:39:27 -0700 (PDT) MIME-Version: 1.0 Received: by 10.12.146.164 with HTTP; Fri, 14 Oct 2016 21:39:27 -0700 (PDT) In-Reply-To: References: From: Dave Taht Date: Fri, 14 Oct 2016 21:39:27 -0700 Message-ID: To: jb Cc: bloat Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Bloat] grading bloat better X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 15 Oct 2016 04:39:28 -0000 On Fri, Oct 14, 2016 at 3:48 PM, jb wrote: > Is this classic buffer bloat on 50 megabit cable modem? Looks like it. > https://www.dslreports.com/forum/r31035315-Weird-speed-test-results-It-fa= lls-off-right-at-the-end > > by extending the download duration to 30 seconds, what looks like > a speed "fall-off at the end" reveals two complete stall/recoveries, and > associated > high latency during the download phase. > > On Thu, Oct 13, 2016 at 2:22 PM, Dave Taht wrote: >> >> Thank you very much for the explanation and the fix. I am confronted >> by the dsltestreports stuff every day on my search for bufferbloat. I >> don't consider it annoying, but as a chance to spot check! >> >> ... >> >> I still might quibble, but a trimmed mean makes more sense than just a >> mean. >> >> Problem I always have is bloat is biased always towards the end of a tes= t. >> Here, >> at 1gbit, it took nearly 20 seconds to start going boom. Maybe we need >> to invent a new distribution (The bloat distribution? The TCP >> distribution)... >> >> You are getting towards a big dataset now. (has it been a year yet?) >> Got anyone lined up for a paper on it? I'd still love it if one day >> someone could take all the data you are filtering out, and plot >> that.... >> >> I imagine the user's test result is cached and not subject to these >> modifications? >> >> On Wed, Oct 12, 2016 at 5:57 PM, jb wrote: >> > It is done >> > under the trimmed mean method, that would be a "C" grade result. >> > >> > >> > >> > On Thu, Oct 13, 2016 at 11:46 AM, jb wrote: >> >> >> >> Actually I think the concept I need is the trimmed mean. >> >> throwing away the highest couple of values (lowest couple are not to = be >> >> thrown away because they can't be errant). >> >> It isn't perfect but it would help. >> >> >> >> On Thu, Oct 13, 2016 at 11:39 AM, jb wrote: >> >>> >> >>> A while ago I changed from mean to median with the reasoning being >> >>> that >> >>> one spike to a crazy level was not representative of bloat but inste= ad >> >>> representative of a network stall or other anomaly. Graphs that were >> >>> nearly >> >>> all good samples with one outlier were being unfairly graded poorly. >> >>> >> >>> But this example has the opposite issue - the median of this set of >> >>> samples is the first half where everything is ok. Hence the good >> >>> score. >> >>> Using a mean would be correct for this sample. >> >>> What should happen is to throw away a couple (max) outliers first, >> >>> then >> >>> do a mean to avoid punishing the results that come in as good but >> >>> include >> >>> one errant measurement. >> >>> >> >>> thanks >> >>> -Justin >> >>> >> >>> On Wed, Oct 12, 2016 at 11:16 PM, Dave Taht >> >>> wrote: >> >>>> >> >>>> This has major bloat happening at the end of the upload test. Which >> >>>> worries me - here, at a gbit. >> >>>> >> >>>> http://www.dslreports.com/speedtest/5284047 >> >>>> >> >>>> -- >> >>>> Dave T=C3=A4ht >> >>>> Let's go make home routers and wifi faster! With better software! >> >>>> http://blog.cerowrt.org >> >>>> _______________________________________________ >> >>>> Bloat mailing list >> >>>> Bloat@lists.bufferbloat.net >> >>>> https://lists.bufferbloat.net/listinfo/bloat >> >>> >> >>> >> >> >> > >> >> >> >> -- >> Dave T=C3=A4ht >> Let's go make home routers and wifi faster! With better software! >> http://blog.cerowrt.org > > --=20 Dave T=C3=A4ht Let's go make home routers and wifi faster! With better software! http://blog.cerowrt.org