From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-x22e.google.com (mail-wm0-x22e.google.com [IPv6:2a00:1450:400c:c09::22e]) (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 B8D163B25E for ; Fri, 14 Oct 2016 18:48:16 -0400 (EDT) Received: by mail-wm0-x22e.google.com with SMTP id d128so7014286wmf.1 for ; Fri, 14 Oct 2016 15:48:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=jouIps/9QEbavfRFR/NrkZaE1qN7yjvG9kTmP/a2jWg=; b=nelJIw5Gs0LzjyPugmM2H2cavw0FfheGohjnWW/FQ6qhKeSoOONjQRjpin8SknvoL+ U6fungEjZsdVwh6/TgFn7ZbsQfL3ihBAJMd3BVjvuMc4R13Kg3ZIXpl5Ux1I+3izCZ6k mx426vPyW3zcvMKN/1stqLg/avzIDR9DekNsevwnGjJNKQTVyDxmgaPhpqPrpzlCLXpM 3cwSZ1vv7fsdwsIIQXaYe6Ky7svdq9+zC9n6JsWhLV8REh8DBuCGYHF91SnGeIrikXZd EZQOcml3XeDws97A2UeYekWoVUJZQZBPBknCxeF45AOMpdBy/ubWKVTbqbi6P/pCEf8N RHig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=jouIps/9QEbavfRFR/NrkZaE1qN7yjvG9kTmP/a2jWg=; b=aIafPH5mv2WSKd/u0prk8ToyZb9VStEhmzyXoGgNgsaLOK0X1VsOdocq4tBsLopdjY 5+PK7SFIM9hwOm26HgGIx9CPYenxN4XaTzjSe8OacwjIJiOeaP1gHxkE2FSUkziHOarW 9zjdWYrxnseYqoY8LG0VGgPniWBKuZqlXlTyWIJyjrLOnaLepolLfRyo7ru7gFF6A1Ak 7IDQMJxXFk59h6fZL2NN7S1XgYYagqVdrvii5zNiCCisWINIu4lGfqAoF2JbQXh+PUQB UA5C27WTi7448EjtLEo2tPJm4UehVDCL3QeOa6trde64WqTLR6FxbRbPWSO9vi7H44A9 veIA== X-Gm-Message-State: AA6/9RnFXmMaXcr/jAikRZ9drVpmMpKf8I+QjJJclE9J6vAqsAH3t2FTF7/zrySJeIedGUs/d7GITF9XFHLNpg== X-Received: by 10.28.141.72 with SMTP id p69mr300893wmd.66.1476485295746; Fri, 14 Oct 2016 15:48:15 -0700 (PDT) MIME-Version: 1.0 Sender: justinbeech@gmail.com Received: by 10.28.207.134 with HTTP; Fri, 14 Oct 2016 15:48:15 -0700 (PDT) In-Reply-To: References: From: jb Date: Sat, 15 Oct 2016 09:48:15 +1100 X-Google-Sender-Auth: brNBVIe1vS56uffTQui3GXiD8C4 Message-ID: To: Dave Taht Cc: bloat Content-Type: multipart/alternative; boundary=001a11470e3491b4c6053edb053e 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: Fri, 14 Oct 2016 22:48:16 -0000 --001a11470e3491b4c6053edb053e Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Is this classic buffer bloat on 50 megabit cable modem? https://www.dslreports.com/forum/r31035315-Weird-speed-test-results-It-fall= s-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 test= . > 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 b= e > >> 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 th= at > >>> one spike to a crazy level was not representative of bloat but instea= d > >>> 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 scor= e. > >>> Using a mean would be correct for this sample. > >>> What should happen is to throw away a couple (max) outliers first, th= en > >>> 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 > --001a11470e3491b4c6053edb053e Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Is this classic buffer bloat on 50 megabit cable modem?


On Thu, Oct 13, 2016 at 2:22 PM, Dave Taht <dave.= taht@gmail.com> wrote:
Than= k 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 test. = 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 <= justin@dslr.net> wrote:
> It is done
> under the trimmed mean method, that would be a "C" grade res= ult.
>
>
>
> On Thu, Oct 13, 2016 at 11:46 AM, jb <justin@dslr.net> 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 <justin@dslr.net> wrote:
>>>
>>> A while ago I changed from mean to median with the reasoning b= eing that
>>> one spike to a crazy level was not representative of bloat but= instead
>>> representative of a network stall or other anomaly. Graphs tha= t were nearly
>>> all good samples with one outlier were being unfairly graded p= oorly.
>>>
>>> But this example has the opposite issue - the median of this s= et of
>>> samples is the first half where everything is ok. Hence the go= od score.
>>> Using a mean would be correct for this sample.
>>> What should happen is to throw away a couple (max) outliers fi= rst, 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 <dave.taht@gmail.com> wrote:
>>>>
>>>> This has major bloat happening at the end of the upload te= st. 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 bette= r software!
>>>> http://blog.cerowrt.org
>>>> _______________________________________________
>>>> Bloat mailing list
>>>> Bloat@lists= .bufferbloat.net
>>>> https://lists.bufferbloat.net/list= info/bloat
>>>
>>>
>>
>



--
Dave T=C3=A4ht
Let's go make home routers and wifi faster! With better software!
ht= tp://blog.cerowrt.org

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