From owner-freebsd-current Sun Jan 17 10:04:21 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id KAA09853 for freebsd-current-outgoing; Sun, 17 Jan 1999 10:04:21 -0800 (PST) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from bright.fx.genx.net (bright.fx.genx.net [206.64.4.154]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id KAA09846 for ; Sun, 17 Jan 1999 10:04:16 -0800 (PST) (envelope-from bright@hotjobs.com) Received: from localhost (bright@localhost) by bright.fx.genx.net (8.9.1/8.9.1) with ESMTP id NAA53090; Sun, 17 Jan 1999 13:09:41 -0500 (EST) (envelope-from bright@hotjobs.com) X-Authentication-Warning: bright.fx.genx.net: bright owned process doing -bs Date: Sun, 17 Jan 1999 13:09:41 -0500 (EST) From: Alfred Perlstein X-Sender: bright@bright.fx.genx.net To: Christian Kuhtz cc: freebsd-current@FreeBSD.ORG Subject: Re: ufs async In-Reply-To: <19990117112925.A19618@oreo.adsu.bellsouth.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Sun, 17 Jan 1999, Christian Kuhtz wrote: > > Hey gang: > > Somebody mentioned the other day that UFS async isn't entirely async, and > that directories are (always) sync. Is that true? not afaik. > Can somebody elaborate on why that is? normal UFS mounts are async in respect to data, however meta-data/directory-ops are done sync so that your filesystem doesn't resemble the aftermath of "squril VS 18-wheeler" in the case of a power outage/crash you CAN mount UFS totally async, but then if you incorrectly shutdown your box prepare to recreate the filesystem (*) in 3.0 you have the option of 'softupdates' if you qualify for the license, look in the /usr/src/contrib/sys/softupdates/README for an explanation. softupdates allow for safe async because writes to the meta-data are ordered in a failsafe manner. -Alfred (*) i used to mount async for builds and compiling at times a while back, i never had massive destruction, but you never know, i suspect renaming your /usr and hitting the reset button would be considered fatal if timed properly > > Cheers, > Chris > > -- > "We are not bound by any concept, we are just bound to make any concept work > better than others." -- Dr. Ferry Porsche > > [Disclaimer: I speak for myself and my views are my own and not in any way to > be construed as the views of BellSouth Corporation. ] > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-current" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message