From owner-freebsd-net@FreeBSD.ORG Mon Oct 5 09:48:32 2009 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A6D471065672 for ; Mon, 5 Oct 2009 09:48:32 +0000 (UTC) (envelope-from rihad@mail.ru) Received: from mx48.mail.ru (mx48.mail.ru [94.100.176.62]) by mx1.freebsd.org (Postfix) with ESMTP id 62C368FC33 for ; Mon, 5 Oct 2009 09:48:32 +0000 (UTC) Received: from [217.25.27.27] (port=63094 helo=[217.25.27.27]) by mx48.mail.ru with asmtp id 1MukBC-000DkE-00; Mon, 05 Oct 2009 13:48:30 +0400 Message-ID: <4AC9C0ED.3020904@mail.ru> Date: Mon, 05 Oct 2009 14:48:29 +0500 From: rihad User-Agent: Mozilla-Thunderbird 2.0.0.22 (X11/20090706) MIME-Version: 1.0 To: Eugene Grosbein References: <4AC8A76B.3050502@mail.ru> <20091005025521.GA52702@svzserv.kemerovo.su> <20091005061025.GB55845@onelab2.iet.unipi.it> <4AC9B400.9020400@mail.ru> <20091005090102.GA70430@svzserv.kemerovo.su> In-Reply-To: <20091005090102.GA70430@svzserv.kemerovo.su> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam: Not detected X-Mras: Ok Cc: freebsd-net@freebsd.org Subject: Re: dummynet dropping too many packets X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 Oct 2009 09:48:32 -0000 Eugene Grosbein wrote: > On Mon, Oct 05, 2009 at 01:53:20PM +0500, rihad wrote: > >> As you can see the drops gradually went away completely at about 4:00 >> a.m., and started coming up at about 10:30 a.m., although at a lower >> rate, probably thanks to me bumping "ipfw ... queue NNN" up to 5000 at >> 10a.m. this morning. The traffic flow between 4a.m. and 10:30a.m., the >> "quiet" times, is about 200-330 mbit/s 5 minute average, without a >> single drop. But after that, in come the drops, no matter how high I set >> the queue. Should I try 10000 slots? 20000? > > First switch from taildrop (default) to GRED, it is designed to fight > your problem. > red | gred w_q/min_th/max_th/max_p Make use of the RED (Random Early Detection) queue management algo- rithm. w_q and max_p are floating point numbers between 0 and 1 (0 not included), while min_th and max_th are integer numbers specify- ing thresholds for queue management (thresholds are computed in bytes if the queue has been defined in bytes, in slots otherwise). The dummynet(4) also supports the gentle RED variant (gred). Do you or someone else know what w_q and max_p are? There's just too much info for me to grasp here: http://www.icir.org/floyd/red.html