From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from uplift.swm.pp.se (swm.pp.se [212.247.200.143]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 0F4303B29E for ; Tue, 27 Nov 2018 06:21:50 -0500 (EST) Received: by uplift.swm.pp.se (Postfix, from userid 501) id D5298B9; Tue, 27 Nov 2018 12:21:48 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=swm.pp.se; s=mail; t=1543317708; bh=X+Ak116GdGyDMEg7DZ5Udtrmp7DbPo8ZJBrhmiCDcWY=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=1cSajg/S/ffKMkZhOg7xFpShBCsN0PTWNDg9g9Ivw2oPBC88M2+TPP66l7XsAlgbn TngTbnjHQ1HptIu/C2wHdu+94rWKjCyRf4d6HFdHGeKETy2y0hivyvMc+t1+hAWn6Y fYAKMzGUOb8rEQvyUFsm/UnR2rhW9C/N18OlbnKM= Received: from localhost (localhost [127.0.0.1]) by uplift.swm.pp.se (Postfix) with ESMTP id D04CEB6; Tue, 27 Nov 2018 12:21:48 +0100 (CET) Date: Tue, 27 Nov 2018 12:21:48 +0100 (CET) From: Mikael Abrahamsson To: Luca Muscariello cc: "Bless, Roland (TM)" , Jonathan Morton , bloat In-Reply-To: Message-ID: References: <65EAC6C1-4688-46B6-A575-A6C7F2C066C5@heistp.net> <86b16a95-e47d-896b-9d43-69c65c52afc7@kit.edu> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) Organization: People's Front Against WWW MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Subject: Re: [Bloat] when does the CoDel part of fq_codel help in the real world? 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: Tue, 27 Nov 2018 11:21:50 -0000 On Tue, 27 Nov 2018, Luca Muscariello wrote: > A BDP is not a large buffer. I'm not unveiling a secret. It's complicated. I've had people throw in my face that I need 2xBDP in buffer size to smoothe things out. Personally I don't want more than 10ms buffer (max), and I don't see why I should need more than that even if transfers are running over hundreds of ms of light-speed-in-medium induced delay between the communicating systems. I have routers that are perfectly capable at buffering packets for hundreds of ms even at hundreds of megabits/s of access speed. I choose not to use them though, and configure them to drop packets much earlier. > My point was that FQ_codel helps to get very close to the optimum w/o > adding useless queueing and latency. With a single queue that's almost > impossible. No, sorry. Just impossible. Right, I realise I wasn't clear I wasn't actually commenting on your specific text directly, my question was more generic. -- Mikael Abrahamsson email: swmike@swm.pp.se