From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bifrost.lang.hm (lang.hm [66.167.227.134]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 29BDB3B29E for ; Mon, 13 Nov 2017 21:08:33 -0500 (EST) Received: from asgard.lang.hm (asgard.lang.hm [10.0.0.100]) by bifrost.lang.hm (8.13.4/8.13.4/Debian-3) with ESMTP id vAE28TfI018461; Mon, 13 Nov 2017 18:08:29 -0800 Date: Mon, 13 Nov 2017 18:08:29 -0800 (PST) From: David Lang X-X-Sender: dlang@asgard.lang.hm To: George Amanakis cc: Jonathan Morton , cake@lists.bufferbloat.net In-Reply-To: Message-ID: References: <87po92aku1.fsf@nemesis.taht.net> <87efph4q0y.fsf@nemesis.taht.net> <87vaihkgr9.fsf@nemesis.taht.net> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII Subject: Re: [Cake] total download rate with many flows X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Nov 2017 02:08:33 -0000 Ingres and Egress are fundamentally different due to the fact that in ingress mode you are having to throw away data that has successfully traversed the bottleneck (deliberatly wasting your limited resource now to avoid having senders bottleneck the queue on the far side of the link) in Egress mode, you aren't doing that, and so you can get much closer to the actual bandwidth. In addition, in Ingress mode, you are always working via second-order effects, you can't slow a transmission directly like you can in egress mode, all you can do is drop packets and wait until the sender notices, retransmits and slows down. Egress has full control of the queues and can send things in any order, and may be able to continually fill the pipe and avoid any timeouts and retransmissions (if the flow is short enough) David Lang