From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa0-x236.google.com (mail-oa0-x236.google.com [IPv6:2607:f8b0:4003:c02::236]) (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 ECC3F21F225 for ; Tue, 25 Feb 2014 07:59:59 -0800 (PST) Received: by mail-oa0-f54.google.com with SMTP id n16so585586oag.41 for ; Tue, 25 Feb 2014 07:59:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=fNdyFT9s8jw5szLyHw6Lzcv+HwYFg/OLKa0+0RO/LHY=; b=kDBuBnanTddMUazlRI+G/uOyn0AjSosjvadd+nGlB+LuVj4KqLbD9zDjQzBRZkfIiF t8DFyqQ7a11zo1wbEIRd/cD6WtazH2r+95BkbyMKvLJ7qOq431KZm8jXl8jYKGpTNjOJ woDlxdjCXGYqmcenGQChhC3HX7aXHVzpRp8Y/nOYY34+sNgxogHWc08k/PLsyoKitxe0 D1/2MtCcbaDLaG8pPfiBMsz1KQz2r0+PIIAb1353XitpHf/27fyARYf7z7Y2GSuLm3DK cnaw/bQavbdL1F40a3XW+kxd4sbv6S9GsUA5rJOiYFD6ZYU09CH1zMdveJwx9gp4V9YJ QgAQ== MIME-Version: 1.0 X-Received: by 10.60.84.199 with SMTP id b7mr1836253oez.55.1393343998960; Tue, 25 Feb 2014 07:59:58 -0800 (PST) Sender: gettysjim@gmail.com Received: by 10.76.84.162 with HTTP; Tue, 25 Feb 2014 07:59:58 -0800 (PST) In-Reply-To: <530C7AFA.2070101@gmail.com> References: <530C7AFA.2070101@gmail.com> Date: Tue, 25 Feb 2014 10:59:58 -0500 X-Google-Sender-Auth: 21uft93VMmf4jZtP5KcFe1HHtgo Message-ID: From: Jim Gettys To: Oliver Niesner Content-Type: multipart/alternative; boundary=089e0102dc821bab7204f33d2e70 Cc: Nicholas Weaver , "cerowrt-devel@lists.bufferbloat.net" Subject: Re: [Cerowrt-devel] uplink_buffer_adjustment 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: Tue, 25 Feb 2014 16:00:00 -0000 --089e0102dc821bab7204f33d2e70 Content-Type: text/plain; charset=ISO-8859-1 On Tue, Feb 25, 2014 at 6:14 AM, Oliver Niesner wrote: > Hi list, > > I use cerowrt (3.10.24-8) direct behind my main dsl Router. > SQM is set and performance is good. > When i used Netalyzr from my smartphone i've got good results. > > > Network buffer measurements (?): Uplink 96 ms, Downlink is good > > But when i use my notebook i get this: > > > Network buffer measurements (?): Uplink 1200 ms, Downlink is good > > I tried even wired connection and set ring buffer rx/tx with ethtool to > 64, but > only minimal change in uplink buffer (1100ms). > > Has anyone an idea, what i can try to get better uplink performance? > Netalyzr uses a UDP based test for "filling the buffers"; it is not responsive to drops/marks at all, the way a TCP test would be. So if you run it, the flows it generates are unresponsive, and indicate the true size of the buffers at the bottleneck link, even though any normal TCP would long since have responded and nothing like that amount of buffering would have taken place. Furthermore, the flow queuing of fq_codel isolates those flows from other flows, and therefore you do not get the bad latency you would otherwise get on those flows. In short, (particularly since fq_codel is deployed in quantity millions by a few ISP's already; it is no longer a fluke to find it only in hacker's hands), Nick Weaver needs to improve netalyzr to detect flow queuing algorithms and make some sense out of the situation. It would be great to monitor the spread of these algorithms around the Internet over the coming years. So it is arguably a "bug" in netalyzr. It is certainly extremely misleading. Nick? - Jim > Regards, > > Oliver > > _______________________________________________ > Cerowrt-devel mailing list > Cerowrt-devel@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cerowrt-devel > --089e0102dc821bab7204f33d2e70 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable


On Tue= , Feb 25, 2014 at 6:14 AM, Oliver Niesner <oliver.niesner@gmail.com= > wrote:
Hi list,

I use cerowrt (3.10.24-8) direct behind my main dsl Router.
SQM is set and performance is good.
When i used Netalyzr from my smartphone i've got good results.

> Network buffer measurements (?): Uplink 96 ms, Downlink is good

But when i use my notebook i get this:

> Network buffer measurements (?): Uplink 1200 ms, Downlink is good

I tried even wired connection and set ring buffer rx/tx with ethtool to 64,= but
only minimal change in uplink buffer (1100ms).

Has anyone an idea, what i can try to get better uplink performance?

Netalyzr uses a UDP based test for "filling the buffers"; it= is not responsive to drops/marks at all, the way a TCP test would be.

So if you run it, the flows it= generates are unresponsive, and indicate the true size of the buffers at t= he bottleneck link, even though any normal TCP would long since have respon= ded and nothing like that amount of buffering would have taken place. =A0Fu= rthermore, the flow queuing of fq_codel isolates those flows from other flo= ws, and therefore you do not get the bad latency you would otherwise get on= those flows.

In short, (particularly since = fq_codel is deployed in quantity millions by a few ISP's already; it is= no longer a fluke to find it only in hacker's hands), Nick Weaver need= s to improve netalyzr to detect flow queuing algorithms and make some sense= out of the situation. =A0It would be great to monitor the spread of these = algorithms around the Internet over the coming years.

So it is arguably a "bug&= quot; in netalyzr. =A0It is certainly extremely misleading.

Nick?

=A0 =A0 =A0 =A0 =A0 =A0 =A0 = =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0- Jim


Regards,

Oliver

_______________________________________________
Cerowrt-devel mailing list
Cerowrt-devel@lists.= bufferbloat.net
https://lists.bufferbloat.net/listinfo/cerowrt-devel

--089e0102dc821bab7204f33d2e70--