From owner-freebsd-questions Thu Sep 30 14:24:41 1999 Delivered-To: freebsd-questions@freebsd.org Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by hub.freebsd.org (Postfix) with ESMTP id 45D80153B0 for ; Thu, 30 Sep 1999 14:24:35 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: (from grog@localhost) by freebie.lemis.com (8.9.3/8.9.0) id GAA23159; Fri, 1 Oct 1999 06:54:19 +0930 (CST) Date: Fri, 1 Oct 1999 06:54:19 +0930 From: Greg Lehey To: Julian Elischer Cc: Trent Nelson , FreeBSD Questions Subject: Re: Vinum/SoftUpdates query. Message-ID: <19991001065418.M496@freebie.lemis.com> References: <19990930150707.J496@freebie.lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: ; from Julian Elischer on Thu, Sep 30, 1999 at 09:03:03AM -0700 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thursday, 30 September 1999 at 9:03:03 -0700, Julian Elischer wrote: > On Thu, 30 Sep 1999, Greg Lehey wrote: >> >> We're currently seeing some problems with soft updates in connection >> with RAID-5, but that's not of any great relevance to your system, >> since you need at least 3 disks for RAID-5. > > What kind of problem, From http://www.lemis.com/vinum/bugs.html: 28 September 1999: We've seen some strange panics when using Vinum RAID-5. The symptoms are: Fatal trap 12: page fault while in kernel mode fault virtual address = 0x0 fault code = supervisor read, page not present instruction pointer = 0x8:0x0 Note particularly the instruction pointer value. This happens during normal file access. In all cases I have investigated, the system was using soft updates. I have one report of a similar panic without soft updates, but it hasn't been substantiated. This problem doesn't happen everywhere, but where it does, it's quite reliable. If you're planning to use this constellation, be sure to test carefully. Technical explanation: A buffer header gets corrupted between the time the top half of the driver issues the request to the disk driver, and when the I/O completes. Currently, the evidence is pointing towards the disk driver, but the corruption is of such an unusual nature that it's difficult to guess what's going on. Status: At the moment, I don't understand how the problem arises, so I don't have a fix. Note that there's no mention of soft updates here. Since the initial report, all of which included soft updates, I've had one report of what seems to be the same thing on a volume without soft updates. > and has anyone told Kirk? Yes, I sent him a message about a week ago. So far no reply. Greg -- When replying to this message, please copy the original recipients. For more information, see http://www.lemis.com/questions.html See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message