From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.taht.net (mail.taht.net [IPv6:2a01:7e00:e000:2d4:f00f:f00f:b33b:b33b]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 1CCA23B2A4 for ; Tue, 26 Nov 2019 21:13:38 -0500 (EST) Received: from nemesis.taht.net (c-71-198-101-102.hsd1.ca.comcast.net [71.198.101.102]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.taht.net (Postfix) with ESMTPSA id 245F821B46; Wed, 27 Nov 2019 02:13:34 +0000 (UTC) From: Dave Taht To: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= Cc: Kan Yan , Rajkumar Manoharan , Kevin Hayes , Make-Wifi-fast , linux-wireless , Yibo Zhao , John Crispin , Johannes Berg , Lorenzo Bianconi , Felix Fietkau References: <20191115014846.126007-1-kyan@google.com> <8736eiam8f.fsf@toke.dk> <87a78p8rz7.fsf@toke.dk> <87muco5gv5.fsf@toke.dk> <87eexvyoy8.fsf@toke.dk> Date: Tue, 26 Nov 2019 18:13:42 -0800 In-Reply-To: <87eexvyoy8.fsf@toke.dk> ("Toke \=\?utf-8\?Q\?H\=C3\=B8iland-J\?\= \=\?utf-8\?Q\?\=C3\=B8rgensen\=22's\?\= message of "Tue, 26 Nov 2019 10:19:43 +0100") Message-ID: <878so2m5gp.fsf@nemesis.taht.net> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Make-wifi-fast] [PATCH v8 0/2] Implement Airtime-based Queue Limit (AQL) X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Nov 2019 02:13:38 -0000 Toke H=C3=B8iland-J=C3=B8rgensen writes: > Kan Yan writes: > >>> Yeah, bpftrace can be a bit of a pain to get running; but it may be >>> worth the investment longer term as well. It really is quite useful! :) >> >> My attempt to build bpftrace didn't work out, so I just got the >> sojourn time using old fashioned trace event. >> The raw trace, parsed data in csv format and plots can be found here: >> https://drive.google.com/open?id=3D1Mg_wHu7elYAdkXz4u--42qGCVE1nrILV >> >> All tests are done with 2 TCP download sessions that oversubscribed >> the link bandwidth. >> With AQL on, the mean sojourn time about ~20000us, matches the default >> codel "target". > > Yeah, since CoDel is trying to control the latency to 20ms, it makes > sense that the value is clustered around that. That means that the > algorithm is working as they're supposed to :) > > While you're running tests, could you do one with the target changed to > 10ms, just to see what it looks like? Both sojourn time values and > throughput would be interesting here, of course. > >> With AQL off, the mean sojourn time is less than 4us even the latency >> is off the charts, just as we expected that fd_codel with mac80211 >> alone is not effective for drivers with deep firmware/hardware queues I hope to take a close look at the iwl ax200 chips soon. Unless someone beats me to it. Can we get these sort of stats out of it? Has anyone looked at the marvell chips of late? > > Yup, also kinda expected; but another good way to visualise the impact. > Nice! > > -Toke > > _______________________________________________ > Make-wifi-fast mailing list > Make-wifi-fast@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/make-wifi-fast