From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-x22e.google.com (mail-qg0-x22e.google.com [IPv6:2607:f8b0:400d:c04::22e]) (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 6FE5821FE91; Fri, 7 Aug 2015 10:35:29 -0700 (PDT) Received: by qgeg42 with SMTP id g42so42726772qge.1; Fri, 07 Aug 2015 10:35:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=xp9YyyT0e2fN4vE6TsNxvpc1uSzwjEVB0SxpWFiE5Aw=; b=ORsXNHuJIkgtS7dnUQ8piqjurH1M76jl852gZbrMHE7RHLTzh5pApYlWSiiAbF50sw CXeyvKTMoA1bsEkfj3QMRi8K3q/KofV153gL0kclTgXHkEC0njhaKS31OqYiY5fW171l B4Vkzy4qUovMKYal6Ce9Nf+9DPDXn5EERv4JiKV4LGmNarEaXLTWzyap5Z/pHeOtn16H AtGDc21sC3qkxOdXOYvdQIuAfQQQ7YLghBKPn6EqV5hamXCTKIZYf9zpBNPtmDokvKY7 cj3tKpScsABx48LS0dtGKx8loz3YyVn+qcV8siNuT0nPNCdP4ScZXVRFjK8J/LYS6kJM Aklg== X-Received: by 10.140.106.137 with SMTP id e9mr14936465qgf.106.1438968928057; Fri, 07 Aug 2015 10:35:28 -0700 (PDT) Received: from richs-mbp-13907.lan ([71.169.176.121]) by smtp.gmail.com with ESMTPSA id 49sm785547qgh.4.2015.08.07.10.35.26 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 07 Aug 2015 10:35:27 -0700 (PDT) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Rich Brown In-Reply-To: <6E08E48D-5D53-48E5-B088-2D1DB5E566AD@gmail.com> Date: Fri, 7 Aug 2015 13:35:25 -0400 Content-Transfer-Encoding: quoted-printable Message-Id: <4DB19372-E89D-4153-B8DC-999555FE0363@gmail.com> References: <356F5FEE-9FBD-4FF9-AC17-86A642D918A4@gmail.com> <5CC1DC90-DFAF-4A4D-8204-16CD4E20D6E3@gmx.de> <4D24A497-5784-493D-B409-F704804326A7@gmx.de> <1438361254.45977158@apps.rackspace.com> <6E08E48D-5D53-48E5-B088-2D1DB5E566AD@gmail.com> To: Jonathan Morton X-Mailer: Apple Mail (2.1878.6) Cc: make-wifi-fast@lists.bufferbloat.net, cerowrt-devel@lists.bufferbloat.net Subject: Re: [Cerowrt-devel] [Make-wifi-fast] [tsvwg] Comments on draft-szigeti-tsvwg-ieee-802-11e 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: Fri, 07 Aug 2015 17:35:57 -0000 Ah..., the bitter bit of the reality sandwich. Yum :-( But Dave's note about Felix's hook for per-station queueing makes it = seem feasible, if only a lot of work. Thanks, all, for the enlightenment! Rich On Aug 7, 2015, at 9:28 AM, Jonathan Morton = wrote: >=20 >> On 7 Aug, 2015, at 15:22, Rich Brown wrote: >>=20 >> - At that time, the wifi driver requests packets from fq_codel until = a) the the fq_codel queues are empty, or b) the wifi frame is full. In = either case, the wifi driver sends what it has. >=20 > There=92s one big flaw with this: if packets are available for = multiple destinations, fq_codel will generally give you a variety pack = of packets for each of them. But a wifi TXOP is for a single = destination, so only some of the packets would be eligible for the same = aggregate frame. >=20 > So what=92s needed is a way for the wifi driver to tell the queue that = it wants packets for the *same* destination as it=92s transmitting to. >=20 >> - Once the transmit opportunity has come around, it's a matter of = microseconds (I assume) to pull in a wifi frame's worth of packets from = fq_codel >=20 > This is hard to guarantee in software in a general-purpose OS. >=20 > - Jonathan Morton >=20