From owner-freebsd-fs Sat Mar 23 21:32:52 2002 Delivered-To: freebsd-fs@freebsd.org Received: from snipe.prod.itd.earthlink.net (snipe.mail.pas.earthlink.net [207.217.120.62]) by hub.freebsd.org (Postfix) with ESMTP id 4379D37B417; Sat, 23 Mar 2002 21:32:49 -0800 (PST) Received: from pool0282.cvx40-bradley.dialup.earthlink.net ([216.244.43.27] helo=mindspring.com) by snipe.prod.itd.earthlink.net with esmtp (Exim 3.33 #1) id 16p0ca-00078v-00; Sat, 23 Mar 2002 21:32:48 -0800 Message-ID: <3C9D64EA.BBE84A89@mindspring.com> Date: Sat, 23 Mar 2002 21:32:26 -0800 From: Terry Lambert X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Robert Watson Cc: Willie Viljoen , freebsd-fs@freebsd.org, freebsd-bugs@freebsd.org Subject: Re: Soft update instability with heavy IO and offboard IDE controller References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Robert Watson wrote: > On Sat, 23 Mar 2002, Terry Lambert wrote: > > Disable write caching on the drives. THis is a FAQ. > > Hmm. I thought the wc bit should only affect this sort of scenario in the > event that the system was actually powered off; otherwise, the hard disk > can still flush to disk gradually as it. From the description, it seems > the system panics, but power is never removed from the drives. That said, > I wouldn't be surprised if the problem goes away on the basis that this > will substantially change system behavior for performance reasons, hiding > whatever subtle bug it is :-). The drive lies about commiting data to stable storage. This blows away all the hard work soft updates does trying to ensure ordering. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message