From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 9AD763B29D for ; Tue, 26 Nov 2019 04:19:50 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1574759989; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=W+Jxe4wUa6taaXTyx/M9wM4rkK/IQNNd01d40LpvJBw=; b=WBmErHtl4SsEwdPIK5U9L+62aZH+ZbW/o+xeoUPXMz1EhsYabggvbY4woCU/wjgR5ovclk 6XycfryLkEjK4OO8ObZMtScGyQ3df8DGE3tqHBx3ODDJ+/DR/J/IwoXnTAAUBuJUbwTKz6 NpZ4DnrZWpBI9LS86h1eMyN0hZIOLC8= Received: from mail-lj1-f197.google.com (mail-lj1-f197.google.com [209.85.208.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-350-3Oy2RNRWOTKJuWlzQHBtiw-1; Tue, 26 Nov 2019 04:19:48 -0500 Received: by mail-lj1-f197.google.com with SMTP id d16so3549431ljo.11 for ; Tue, 26 Nov 2019 01:19:48 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=OHk3QyZlc+rm4lFfxeoDeCGOk4m7yPb7g+ZsqulMHdw=; b=Cjbn4KyOk/uozkA9qVjAas5yi5LrVCitEfdtvK5ybyAzSenOqKGoc2HgZME9h9yE/8 VHueARPc7EKCoKnqx4EX8Rl5tdgneEecCvTlv1AlMvwxgzEMyre+XjIVEz9MWhIKH+J8 OFF/xcU0nVQUxpdDduZ2QDJVvRR7T6KCr5yL6jj9BDoOwnvdbc9ZyWettzboSaJo2iF2 sHtN78/dx9mAk+lqor2cTSFn1kN5pG9fFtAlHgi3Lt7Ta4W32xVI3foOK7X+6AoaZNxQ 227svz4nYlkNV9F4WabnOlaJr/emjsOWSWaKozn1fD3Sa6JsdOKSXPIlHqB0aC8kFH6f dd5w== X-Gm-Message-State: APjAAAX68tzWoUMlYeAnxJOIeo41fKRYj8TMHmFGcA5etoTETTtrrp5q hwk7lzenA7VEAfuHLNB1thISmBU+ZPktfQL19QhccqoAs57jkhSVNw0RkKnzChs1uesMbtxemoR lfPgfN1AkF/GEuZMWLO2CvEgSNEdR6ahJmiY= X-Received: by 2002:ac2:5999:: with SMTP id w25mr23601723lfn.42.1574759985550; Tue, 26 Nov 2019 01:19:45 -0800 (PST) X-Google-Smtp-Source: APXvYqwoLhXuBNTaChzNFc9fdd9sulEQ6j+4V7Nqx9wfEw69Kf7LMshjczbh40km3d6Hx8mRgN0jrQ== X-Received: by 2002:ac2:5999:: with SMTP id w25mr23601698lfn.42.1574759985192; Tue, 26 Nov 2019 01:19:45 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk ([2a0c:4d80:42:443::2]) by smtp.gmail.com with ESMTPSA id g5sm5180757ljn.101.2019.11.26.01.19.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Nov 2019 01:19:44 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 64DFF1818BF; Tue, 26 Nov 2019 10:19:43 +0100 (CET) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Kan Yan Cc: Dave Taht , Rajkumar Manoharan , Kevin Hayes , Make-Wifi-fast , linux-wireless , Yibo Zhao , John Crispin , Johannes Berg , Lorenzo Bianconi , Felix Fietkau In-Reply-To: References: <20191115014846.126007-1-kyan@google.com> <8736eiam8f.fsf@toke.dk> <87a78p8rz7.fsf@toke.dk> <87muco5gv5.fsf@toke.dk> X-Clacks-Overhead: GNU Terry Pratchett Date: Tue, 26 Nov 2019 10:19:43 +0100 Message-ID: <87eexvyoy8.fsf@toke.dk> MIME-Version: 1.0 X-MC-Unique: 3Oy2RNRWOTKJuWlzQHBtiw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain 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: Tue, 26 Nov 2019 09:19:50 -0000 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. Yup, also kinda expected; but another good way to visualise the impact. Nice! -Toke