From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sonic310-13.consmr.mail.ir2.yahoo.com (sonic310-13.consmr.mail.ir2.yahoo.com [77.238.177.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 96D533CB35 for ; Thu, 2 Nov 2017 12:58:37 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.fr; s=s2048; t=1509641916; bh=bZhKdH/JOqgqNsfoqwQgS1afbtxGXyxOpw64j7Ch6aw=; h=Subject:References:To:From:Date:In-Reply-To:From:Subject; b=lg2//tW04DhpINCBVxWdKG9CGYue3z7p/UpI6bafVga/WKvnJ1uEGfxL4GbrG5VISgLrCfwzP/9t1HWVdsQ1besdBS8iOEl9ImO++U2SmAdJVGtaHy0SN1jw2NlMieZO8aOWGsPeQeWBGy4gvwIC5kqMz/1LPMYq/8OrRge19tsaZB6yl7t2+YuivFmrg4x/cQSGt0Ewskzzcl3fcrcuV3N4d+I4B7Ki8cjpIB3DEeSObtV29DYlRzBH3+x4s5k90aNHp6n1+K5XtRBtRFQW1qe3pXb8Ami9N/cvapU7Uiql3dHGDkzxt8JjTXEUJzG6QMJjMT0OqLHuDRtovezWkQ== X-YMail-OSG: Z3dvwjQVM1nH1trV9ikw.799FaeEn_EnKHA._jXQRyBHof091UoMsatRNZXHPSM FAiwl4pWpuyTPySDc1oRoM6C8vCiOZMx214l3DW7smsEGHh76pdg11b4UuifQbJIVXJHQ90cXd6p kHWGxJANo_SUf0fi3bHMLCtobk16p01P9vV9ZYvh9UUHX40M32SxlEpInxVgwGLS.33buqSDDYAy 7QV17hCcaFAm6iw4wjX2cDWZ8lb7HTgf.vmxUOCaAc3r.Gkc4ovG5cU6sTJDiwMmA9_DhH.AKFRo aJXJh.jalwpoKhDRdX98df.Hq1_YoNmHBQ5HpyqJ.iAAGSWRQq7jet00M7dughbnpZmhM97zbFSN RpNa0w3eyayJO.ZrbUcLcoE4YBD_zSYxi03vOOFy8rSzp80gyqKRH9uDgr3jribigUmuQsUlupJ5 t2kwptmXDQWcBjGx5NyNsA7tgfIF.0A5qqV7V8RfsuDPOCphSVyEQZrnyFeIMFWwYc8R3c447S3A XTcKGL3gXRO8eIn_nVHUHKjC1jjODoRjmYx_Nt4EAR3Zl5BIQbtqSa35LQ19M4D.ssFfc.6KHOHE bPw-- Received: from sonic.gate.mail.ne1.yahoo.com by sonic310.consmr.mail.ir2.yahoo.com with HTTP; Thu, 2 Nov 2017 16:58:36 +0000 Received: from [127.0.0.1] by smtp121.mail.ir2.yahoo.com with NNFMP; 02 Nov 2017 16:58:34 -0000 X-Yahoo-Newman-Id: 236147.15187.bm@smtp121.mail.ir2.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: Z3dvwjQVM1nH1trV9ikw.799FaeEn_EnKHA._jXQRyBHof0 91UoMsatRNZXHPSMFAiwl4pWpuyTPySDc1oRoM6C8vCiOZMx214l3DW7smsE GHh76pdg11b4UuifQbJIVXJHQ90cXd6pkHWGxJANo_SUf0fi3bHMLCtobk16 p01P9vV9ZYvh9UUHX40M32SxlEpInxVgwGLS.33buqSDDYAy7QV17hCcaFAm 6iw4wjX2cDWZ8lb7HTgf.vmxUOCaAc3r.Gkc4ovG5cU6sTJDiwMmA9_DhH.A KFRoaJXJh.jalwpoKhDRdX98df.Hq1_YoNmHBQ5HpyqJ.iAAGSWRQq7jet00 M7dughbnpZmhM97zbFSNRpNa0w3eyayJO.ZrbUcLcoE4YBD_zSYxi03vOOFy 8rSzp80gyqKRH9uDgr3jribigUmuQsUlupJ5t2kwptmXDQWcBjGx5NyNsA7t gfIF.0A5qqV7V8RfsuDPOCphSVyEQZrnyFeIMFWwYc8R3c447S3AXTcKGL3g XRO8eIn_nVHUHKjC1jjODoRjmYx_Nt4EAR3Zl5BIQbtqSa35LQ19M4D.ssFf c.6KHOHEbPw-- X-Yahoo-SMTP: R8REcOaswBA8tpUVQfvLNOMJ0vXRwYHSeLQ- References: <50453bcb-dc99-ed8e-7a9b-e00ccbcdb550@yahoo.fr> <026B80D8-2452-4E9E-A85E-4FBD6BFB25A1@gmx.de> To: Bloat@lists.bufferbloat.net From: Y Message-ID: Date: Fri, 3 Nov 2017 01:58:29 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <026B80D8-2452-4E9E-A85E-4FBD6BFB25A1@gmx.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Subject: Re: [Bloat] Tuning fq_codel: are there more best practices for slow connections? (<1mbit) X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 02 Nov 2017 16:58:37 -0000 Hi ,Moeller. Fomula of target is 1643 bytes / 810kbps = 0.015846836. It added ATM linklayer padding. 16ms plus 4ms as my sence :P My connection is 12mbps/1mbps ADSL PPPoA line. and I set 7Mbps/810kbps for bypass router buffer. I changed Target 27ms Interval 540ms as you say( down delay plus upload delay). It works well  , now . Thank you. Yutaka. On 2017年11月02日 17:25, Sebastian Moeller wrote: > Hi Y. > > >> On Nov 2, 2017, at 07:42, Y wrote: >> >> hi. >> >> My connection is 810kbps( <= 1Mbps). >> >> This is my setting For Fq_codel, >> quantum=300 >> >> target=20ms >> interval=400ms >> >> MTU=1478 (for PPPoA) >> I cannot compare well. But A Latency is around 14ms-40ms. > Under full saturation in theory you would expect the average latency to equal the sum of upstream target and downstream target (which in your case would be 20 + ???) in reality I often see something like 1.5 to 2 times the expected value (but I have never inquired any deeper, so that might be a measuring artifact)... > > Best Regards > > >> Yutaka. >> >> On 2017年11月02日 15:01, cloneman wrote: >>> I'm trying to gather advice for people stuck on older connections. It appears that having dedictated /micromanged tc classes greatly outperforms the "no knobs" fq_codel approach for connections with slow upload speed. >>> >>> When running a single file upload @350kbps , I've observed the competing ICMP traffic quickly begin to drop (fq_codel) or be delayed considerably ( under sfq). From reading the tuning best practices page is not optimized for this scenario. (<2.5mbps) >>> (https://www.bufferbloat.net/projects/codel/wiki/Best_practices_for_benchmarking_Codel_and_FQ_Codel/) fq_codel >>> >>> Of particular concern is that a no-knobs SFQ works better for me than an untuned codel ( more delay but much less loss for small flows). People just flipping the fq_codel button on their router at these low speeds could be doing themselves a disservice. >>> >>> I've toyed with increasing the target and this does solve the excessive drops. I haven't played with limit and quantum all that much. >>> >>> My go-to solution for this would be different classes, a.k.a. traditional QoS. But , wouldn't it be possible to tune fq_codel punish the large flows 'properly' for this very low bandwidth scenario? Surely <1kb ICMP packets can squeeze through properly without being dropped if there is 350kbps available, if the competing flow is managed correctly. >>> >>> I could create a class filter by packet length, thereby moving ICMP/VoIP to its own tc class, but this goes against "no knobs" it seems like I'm re-inventing the wheel of fair queuing - shouldn't the smallest flows never be delayed/dropped automatically? >>> >>> Lowering Quantum below 1500 is confusing, serving a fractional packet in a time interval? >>> >>> Is there real value in tuning fq_codel for these connections or should people migrate to something else like nfq_codel? >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> _______________________________________________ >>> Bloat mailing list >>> >>> Bloat@lists.bufferbloat.net >>> https://lists.bufferbloat.net/listinfo/bloat >> _______________________________________________ >> Bloat mailing list >> Bloat@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/bloat