From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 13A3C138330 for ; Wed, 21 Sep 2016 20:19:27 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 77578E099D; Wed, 21 Sep 2016 20:19:14 +0000 (UTC) Received: from blaine.gmane.org (unknown [195.159.176.226]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 4C423E090B for ; Wed, 21 Sep 2016 20:19:13 +0000 (UTC) Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1bmnyz-0006zA-JL for gentoo-user@lists.gentoo.org; Wed, 21 Sep 2016 22:19:05 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: gentoo-user@lists.gentoo.org From: Kai Krakow Subject: [gentoo-user] Re: TCP Queuing problem Date: Wed, 21 Sep 2016 22:18:39 +0200 Message-ID: <20160921221839.29ceae91@jupiter.sol.kaishome.de> References: <20160921060118.759d94ba@jupiter.sol.kaishome.de> <20160921212913.352eae72@jupiter.sol.kaishome.de> <20160921214138.3ca8a146@jupiter.sol.kaishome.de> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@blaine.gmane.org X-Newsreader: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) X-Archives-Salt: 1af7dd16-ce01-49c1-bc31-40ded78ab283 X-Archives-Hash: 523ded26f19251b7c53605faa786cf81 Am Wed, 21 Sep 2016 12:53:17 -0700 schrieb Grant : > [...] > [...] > >> > >> You may want to set the default congestion control to fq-codel > >> (it's in the kernel) if you're using DSL links. This may help your > >> problem a little bit. It is most effective if you deploy traffic > >> shaping at the same time. There was once something like > >> wondershaper. Trick is to get the TCP queuing back inside your > >> router (that is where you deployed pppoe) as otherwise packets > >> will queue up in the modem (dsl modems use huge queues by > >> default). This works by lowering the uplink bandwith to 80-90% of > >> measured maximum upload (the excess bandwidth is for short bursts > >> of traffic). Traffic shaping now re-orders the packets. It should > >> send ACK and small packets first. This should solve your queuing > >> problem. > >> > >> Between each step check dslreports.com for bufferbloat. I'm > >> guessing it is currently way above 1000 ms while it should stay > >> below 20-50 ms for dsl. > >> > >> The fq-codel congestion control fights against buffer bloat. But it > >> can only effectively work if you're doing traffic shaping at least > >> on your uplink (downlink may or may not be worth the effort > >> depending on your use-case). > >> > >> Additionally, you can lower the priority of icmp-echo-reply this > >> way so during icmp flooding your uplink will still work. > >> > >> This link may help you: > >> https://www.bufferbloat.net/projects/codel/wiki/Cake/ > > > > And this: > > https://github.com/tohojo/sqm-scripts > > > I haven't mentioned it yet, but several times I've seen the website > perform fine all day until I browse to it myself and then all of a > sudden it's super slow for me and my third-party monitor. WTF??? I had a similar problems once when routing through a IPsec VPN tunnnel. I needed to reduce MTU in front of the tunnel to make it work correctly. But I think your problem is different. Does the http server backlog on the other side? Do you have performance graphs for other parts of the system to see them in relation? Maybe some router on the path doesn't work as expected. -- Regards, Kai Replies to list-only preferred.