From owner-freebsd-current Wed Dec 15 23:58:58 1999 Delivered-To: freebsd-current@freebsd.org Received: from celery.dragondata.com (celery.dragondata.com [205.253.12.6]) by hub.freebsd.org (Postfix) with ESMTP id C96CC14FF5 for ; Wed, 15 Dec 1999 23:58:42 -0800 (PST) (envelope-from toasty@celery.dragondata.com) Received: (from toasty@localhost) by celery.dragondata.com (8.9.3/8.9.3) id BAA87332; Thu, 16 Dec 1999 01:58:52 -0600 (CST) (envelope-from toasty) From: Kevin Day Message-Id: <199912160758.BAA87332@celery.dragondata.com> Subject: Re: Serious server-side NFS problem To: phk@critter.freebsd.dk (Poul-Henning Kamp) Date: Thu, 16 Dec 1999 01:58:52 -0600 (CST) Cc: dillon@apollo.backplane.com (Matthew Dillon), gallatin@cs.duke.edu (Andrew Gallatin), freebsd-current@FreeBSD.ORG In-Reply-To: <14567.945330659@critter.freebsd.dk> from "Poul-Henning Kamp" at Dec 16, 1999 08:50:59 AM X-Mailer: ELM [version 2.5 PL1] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > In message <199912160743.XAA49890@apollo.backplane.com>, Matthew Dillon writes: > > > >:> NFS uses the kernel 'boottime' structure to generate its version id. > >:> Now normally you might believe that this structure, once set, will > >:> never change. The authors of NFS certainly make that assumption! > >: > >:Is this another case of "lets assume the time of day is a random number" or > >:is there any underlying assumption about time in this ? > >: > >:-- > >:Poul-Henning Kamp FreeBSD coreteam member > >:phk@FreeBSD.ORG "Real hackers run -current on their laptop." > > > > It basically needs to be a unique for each server reboot in order > > to allow clients to resynchronize. > > Ok, then I suggest that you cache a copy of the boottime in the NFS > code for this purpose. > Ack, I was using this very same thing for several devices in an isolated peer-to-peer network to decide who the 'master' was. (Whoever had been up longest knew more about the state of the network) Having this change could cause weirdness for me too... I assumed (without checking *thwap*) that boottime was a constant. Perhaps a 'real_boottime' or 'unadjusted_boottime' that gets copied after 'boottime' gets initialized so that others can use it, not just NFS? :) Kevin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message