From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-x22b.google.com (mail-ob0-x22b.google.com [IPv6:2607:f8b0:4003:c01::22b]) (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 BDFB521F82B for ; Tue, 28 Jul 2015 07:44:18 -0700 (PDT) Received: by obdeg2 with SMTP id eg2so85867649obd.0 for ; Tue, 28 Jul 2015 07:44:17 -0700 (PDT) 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=ccMd7V/NRJxPMP6Op351PH5efxgnpGBGYDQ2nYqL7FY=; b=dnrsNzF/rajIVt8n9P9dNbPrzzXgtPfQ+vKnctjynfFyo9KkI/KJrhrzDlTS/VIkbW +H3oIRJ9w+hqUTPNQ6bLRcJWAPlCA/jpu4n4w+XjsyUw+/di7lkVHfQIkXdnjxzV3cgz H6U5nVgkKgd2bjUVG1N4zFMODeSdKHdwcJo3XhFzUxNBVFWhLGqrH8r1pQFXcZORS1qH UmQ7LeTKbQk3XIEt1gb/i74olOS/Q302lg60yDvDd1L50FU/rfUZDr1Cn0UUHO4ONnXe n61T2FAFZYpb1Qd/dFlytqPh0CLCQdbp5/uSXrzk7KYyPMwt6CKPAfnRtpXbMKFllqDP ERmw== MIME-Version: 1.0 X-Received: by 10.182.95.69 with SMTP id di5mr34398186obb.73.1438094657634; Tue, 28 Jul 2015 07:44:17 -0700 (PDT) Received: by 10.202.73.2 with HTTP; Tue, 28 Jul 2015 07:44:17 -0700 (PDT) In-Reply-To: <87a8ugqvid.wl-jch@pps.univ-paris-diderot.fr> References: <87a8ugqvid.wl-jch@pps.univ-paris-diderot.fr> Date: Tue, 28 Jul 2015 16:44:17 +0200 Message-ID: From: Dave Taht To: Juliusz Chroboczek Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Cc: bloat Subject: Re: [Bloat] AQM and PPP on Linux 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: Tue, 28 Jul 2015 14:44:47 -0000 On Tue, Jul 28, 2015 at 3:09 PM, Juliusz Chroboczek wrote: > I'm currently away from home, and using a 3G modem for Internet access. > I've found out that both NetworkManager and wvdial/pppd setup the > interface to use pfifo_fast (with a qlen of a mere 3 packets!). Setting > fq_codel manually appears to work fine, but needs to be redone every time > the modem has a hiccup. > > Is that the expected behaviour? Shouldn't we be pushing patches somewher= e > to change the default? 1) The ppp driver was debloated by david woodhouse way back when. However, the netusb-related drivers, and the 3g devices themselves, contain oft-huge buffers that reduce the effectiveness of any aqm or fq system, sometimes to immeasurability. I would be very interested in flent benchmarks of your 3g device with the 3 packet txqueue and with fq_codel, for the tcp_upload, rrul, and rrul_be tests. 2) Most advanced qdiscs ignore txqueuelen entirely. 3) Usually you can add a script in /etc/network/ifpreup.d or ifup.d to do extra stuff you want. 4) setting the default qdisc to be fq_codel in the sysctl works on most dynamically created devices, but does not work on devices that come up at boot time before the sysctls have a chance to run and the modprobes to complete. This is why fedora 22, for example, compiled in fq_codel statically, rather than dynamically. > -- Juliusz > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat --=20 Dave T=C3=A4ht worldwide bufferbloat report: http://www.dslreports.com/speedtest/results/bufferbloat And: What will it take to vastly improve wifi for everyone? https://plus.google.com/u/0/explore/makewififast