From owner-freebsd-net@FreeBSD.ORG Wed Oct 7 16:49:54 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 86B8F1065696 for ; Wed, 7 Oct 2009 16:49:54 +0000 (UTC) (envelope-from julian@elischer.org) Received: from outI.internet-mail-service.net (outi.internet-mail-service.net [216.240.47.232]) by mx1.freebsd.org (Postfix) with ESMTP id 5F9638FC15 for ; Wed, 7 Oct 2009 16:49:54 +0000 (UTC) Received: from idiom.com (mx0.idiom.com [216.240.32.160]) by out.internet-mail-service.net (Postfix) with ESMTP id B9C06B98A1; Wed, 7 Oct 2009 09:49:54 -0700 (PDT) X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e Received: from julian-mac.elischer.org (home.elischer.org [216.240.48.38]) by idiom.com (Postfix) with ESMTP id 324F82D601E; Wed, 7 Oct 2009 09:49:53 -0700 (PDT) Message-ID: <4ACCC6B3.3020903@elischer.org> Date: Wed, 07 Oct 2009 09:49:55 -0700 From: Julian Elischer User-Agent: Thunderbird 2.0.0.23 (Macintosh/20090812) MIME-Version: 1.0 To: rihad References: <4AC9E29B.6080908@mail.ru> <20091005123230.GA64167@onelab2.iet.unipi.it> <4AC9EFDF.4080302@mail.ru> <4ACA2CC6.70201@elischer.org> <4ACAFF2A.1000206@mail.ru> <4ACB0C22.4000008@mail.ru> <20091006100726.GA26426@svzserv.kemerovo.su> <4ACB42D2.2070909@mail.ru> <20091006142152.GA42350@svzserv.kemerovo.su> <4ACB6223.1000709@mail.ru> <20091006161240.GA49940@svzserv.kemerovo.su> <4ACC5563.602@mail.ru> <4ACC56A6.1030808@mail.ru> <4ACC5DEC.1010006@mail.ru> <4ACC65A0.7030900@mail.ru> <4ACC8CC8.8050403@mail.ru> <4ACCA92A.9070803@mail.ru> In-Reply-To: <4ACCA92A.9070803@mail.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Eugene Grosbein , Robert Watson , Luigi Rizzo , 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: Wed, 07 Oct 2009 16:49:54 -0000 rihad wrote: > Robert Watson wrote: > >> I would suggest making just the HZ -> 4000 change for now and see how >> it goes. >> > OK, I will try testing HZ=4000 tomorrow morning, although I'm pretty > sure there still will be some drops. > >>> Can someone please say how to increase the "ifnet transmit queue sizes"? >> >> Unfortunately, I fear that this is driver-specific, and in the case of >> bce requires a recompile. In the driver init code in if_bce, the >> following code appears: >> >> ifp->if_snd.ifq_drv_maxlen = USABLE_TX_BD; >> IFQ_SET_MAXLEN(&ifp->if_snd, ifp->if_snd.ifq_drv_maxlen); >> IFQ_SET_READY(&ifp->if_snd); >> >> Which evaluates to a architecture-specific value due to varying >> pagesize. You might just try forcing it to 1024. >> > I think I'll try this too, if HZ=4000 doesn't help, thanks a lot. > In the long run we'll switch to some high-quality 10 GiGE cards. for output.. It may still be possible for the output queues to be overrun as teh bursts from dummynet can be much faster than even 10G hardware can dispose of the data.