From owner-freebsd-net@FreeBSD.ORG Wed Feb 11 08:07:16 2004 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id CE9E816A4CE for ; Wed, 11 Feb 2004 08:07:16 -0800 (PST) Received: from relay.pair.com (relay.pair.com [209.68.1.20]) by mx1.FreeBSD.org (Postfix) with SMTP id 6A9E743D2F for ; Wed, 11 Feb 2004 08:07:16 -0800 (PST) (envelope-from silby@silby.com) Received: (qmail 94341 invoked from network); 11 Feb 2004 16:07:15 -0000 Received: from niwun.pair.com (HELO localhost) (209.68.2.70) by relay.pair.com with SMTP; 11 Feb 2004 16:07:15 -0000 X-pair-Authenticated: 209.68.2.70 Date: Wed, 11 Feb 2004 10:07:13 -0600 (CST) From: Mike Silbersack To: richard@wendland.org.uk In-Reply-To: <200402111335.NAA09040@starburst.demon.co.uk> Message-ID: <20040211100522.T1798@odysseus.silby.com> References: <200402111335.NAA09040@starburst.demon.co.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: Bjorn Eikeland cc: freebsd-net@freebsd.org Subject: Re: dummynet = local taffic > 100ms - help! X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 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, 11 Feb 2004 16:07:16 -0000 On Wed, 11 Feb 2004, Richard Wendland wrote: > Well, with HZ=10000 RFC1323 TCP connections will stop after 59.7 hours, > with HZ=100000 after 6 hours. For those with long running TCP connections > (eg remote backup) that could be a big deal. See 4.2.3 of RFC1323. > > It does seem quite a few people want HZ>1000 so I think the time has > come to isolate the TCP timestamp option clock from the HZ value to > avoid this problem. For now they should set net.inet.tcp.rfc1323=0 to > avoid breaking RFC1323. > > Note this doesn't affect routed packets, only TCP connections to/from > that host. > > Tom Pavel sent some patches to this list on 14 Jan 2004 that he has been > using to overcome this HZ/RFC1323 problem. > > Richard > -- > Richard Wendland richard@wendland.org.uk I'm aware of those patches, looking at and committing them is on my to-do list. I don't have any immediate plans to work on it, although I will make sure to get it in before 5.3. Mike "Silby" Silbersack