From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from korolev.univ-paris7.fr (korolev.univ-paris7.fr [IPv6:2001:660:3301:8000::1:2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id F2B033B2A4 for ; Sun, 3 Dec 2017 14:53:34 -0500 (EST) Received: from mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [81.194.30.253]) by korolev.univ-paris7.fr (8.14.4/8.14.4/relay1/75695) with ESMTP id vB3JrXQ0002214; Sun, 3 Dec 2017 20:53:33 +0100 Received: from mailhub.math.univ-paris-diderot.fr (localhost [127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTP id BCCC8EC86D; Sun, 3 Dec 2017 20:53:33 +0100 (CET) X-Virus-Scanned: amavisd-new at math.univ-paris-diderot.fr Received: from mailhub.math.univ-paris-diderot.fr ([127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id 3jMbp-R1eGxs; Sun, 3 Dec 2017 20:53:32 +0100 (CET) Received: from trurl.irif.fr (unknown [78.194.40.74]) (Authenticated sender: jch) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTPSA id E3493EB217; Sun, 3 Dec 2017 20:53:32 +0100 (CET) Date: Sun, 03 Dec 2017 20:53:32 +0100 Message-ID: <87d13vtwoz.wl-jch@irif.fr> From: Juliusz Chroboczek To: Mikael Abrahamsson Cc: bloat@lists.bufferbloat.net In-Reply-To: References: <7B92DF4D-B6B5-4A64-9E10-119DCA2D4A6F@ifi.uio.no> <1512037480.19682.10.camel@gmail.com> <6b494910-1373-afb0-5b93-99b725391fb3@gmail.com> <87wp2638yo.fsf@toke.dk> <87tvxa36sn.fsf@toke.dk> <87po7ygxai.fsf@nemesis.taht.net> <87shcui3ni.wl-jch@irif.fr> <87shcs9k0v.wl-jch@irif.fr> <87po7vud6q.wl-jch@irif.fr> User-Agent: Wanderlust/2.15.9 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (korolev.univ-paris7.fr [194.254.61.138]); Sun, 03 Dec 2017 20:53:33 +0100 (CET) X-Miltered: at korolev with ID 5A24563D.000 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-j-chkmail-Enveloppe: 5A24563D.000 from mailhub.math.univ-paris-diderot.fr/mailhub.math.univ-paris-diderot.fr/null/mailhub.math.univ-paris-diderot.fr/ X-j-chkmail-Score: MSGID : 5A24563D.000 on korolev.univ-paris7.fr : j-chkmail score : . : R=. U=. O=. B=0.000 -> S=0.000 X-j-chkmail-Status: Ham Subject: Re: [Bloat] [Make-wifi-fast] benefits of ack filtering 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: Sun, 03 Dec 2017 19:53:35 -0000 > I can buy 300/10 megabit/s access from my cable provider. Don't! > If I understand correctly, DOCSIS has ~1ms sending opportunities > upstream. So sending more than 1kPPS of ACKs is meaningless, as these ACKs > will just come back to back at wire-speed as the CMTS receives them from > the modem in chunks. So instead, the cable modem just deletes all the > sequential ACKs and doesn't even send these back-to-back ones. If true -- then it's horrible. > LTE works the same, it's also frequency divided and TDM, so I can see the > same benefit there of culling sequential ACKs sitting there in the > buffer. I don't know if this is done though. I cannot find anything about Ack compression in LTE. (The PDCP protocol does header compression, so that's the place I'm looking.) -- Juliusz