From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cl3.bcs-hosting.net (cl3.bcs-hosting.net [3.11.37.202]) (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 025BB3B2A4 for ; Wed, 29 Apr 2020 09:37:03 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=bobbriscoe.net; s=default; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:MIME-Version:Date:Message-ID:References:Cc:To:Subject:From:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=B8N1XIDqy2gKcMS8h+svlspEh1AXECB1Lvs820nx/VY=; b=Yj9M5GlbYjZsU85KLeGJoExhIY saeMeDOk6vXZD/S6Tta3GTQ0Dj5yVNdbm1yXWOEeu3KnpWsqAI+YZu2D/ZDIn3Mn4ELJpUMKmLynB j2Vz5PHCN1gYULtBqlT0bRKcQapz9eGqLZM7jKXbvYSg7y+C9kGyyyS4L1r0qc2FnhZbkm9qmwVzK c0xTZh2DuTziwzYSlEZS4LpeW0uYfq+k8s2cnMBDgGdPjVNP1xiSqciLU3UwNuRjPii29erZRZWxM Nrjro4Z6cdYb2aeIsfrYMRNGoafdJUusH4RLq40qTbHfDCnv2R7LJcvEVS9LBX9VTbpSH6zGvdGJP JLZM0Yzg==; Received: from [31.185.128.97] (port=49984 helo=[192.168.0.6]) by cl3.bcs-hosting.net with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1jTmta-003pPZ-QO; Wed, 29 Apr 2020 14:37:02 +0100 From: Bob Briscoe To: Jonathan Morton Cc: Dave Taht , ECN-Sane , tsvwg IETF list References: <6d925e3b-2781-0fb1-6936-7a6c006b9a21@bobbriscoe.net> <00A6CD68-E37B-4505-BB96-476509937AFC@gmail.com> Message-ID: <537a840b-4c71-4ad2-8421-32c248eb69fa@bobbriscoe.net> Date: Wed, 29 Apr 2020 14:37:02 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <00A6CD68-E37B-4505-BB96-476509937AFC@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-GB X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cl3.bcs-hosting.net X-AntiAbuse: Original Domain - lists.bufferbloat.net X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - bobbriscoe.net X-Get-Message-Sender-Via: cl3.bcs-hosting.net: authenticated_id: in@bobbriscoe.net X-Authenticated-Sender: cl3.bcs-hosting.net: in@bobbriscoe.net X-Source: X-Source-Args: X-Source-Dir: Subject: Re: [Ecn-sane] Fwd: my backlogged comments on the ECT(1) interim call X-BeenThere: ecn-sane@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussion of explicit congestion notification's impact on the Internet List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Apr 2020 13:37:04 -0000 Jonathan, On 29/04/2020 10:49, Jonathan Morton wrote: >> On 29 Apr, 2020, at 12:31 pm, Bob Briscoe wrote: >> >>> Can the L4S and SCE folk run the rrul test some day soon? Please? >> [BB] Does this measure the delay of every packet, so we can measure delay percentiles? > As shown in our test results, Flent (which implements the RRUL test) is indeed now capable of tracking the latency experienced by individual TCP flows. It does not do so at the packet level, but at the socket level. > > Of course it is also possible to capture the traffic and analyse the traces offline, if you really do want packet-level detail. 1. So, why do you continue to use this approach? It hides all the larger delays underneath a moving average. This seems more designed to hide inconsistent delay results than to measure them. If a real-time application waited only for the median delay before rendering, it would have to discard the 50% of traffic in the upper median! TCP also delivers nothing until the more delayed packets have been delivered to get the stream in order. So median (or mean) delay is a meaningless metric. 2. I also notice you didn't address Dave's point about using short flows as well as long. I don't believe I have ever seen a test from you or PeteH with anything but long flows. 3. I should add that I know you personally have tried to address the asymmetric capacity problem with the ACK thinning in CAKE. Bob > - Jonathan Morton > -- ________________________________________________________________ Bob Briscoehttp://bobbriscoe.net/