From owner-freebsd-current Sat Oct 5 10:49:27 2002 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B628537B401; Sat, 5 Oct 2002 10:49:26 -0700 (PDT) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.208.78.105]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5541943E4A; Sat, 5 Oct 2002 10:49:26 -0700 (PDT) (envelope-from kargl@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (localhost [127.0.0.1]) by troutmask.apl.washington.edu (8.12.6/8.12.5) with ESMTP id g95HnQ4G014503; Sat, 5 Oct 2002 10:49:26 -0700 (PDT) (envelope-from kargl@troutmask.apl.washington.edu) Received: (from kargl@localhost) by troutmask.apl.washington.edu (8.12.6/8.12.6/Submit) id g95HnQwb014502; Sat, 5 Oct 2002 10:49:26 -0700 (PDT) From: "Steven G. Kargl" Message-Id: <200210051749.g95HnQwb014502@troutmask.apl.washington.edu> Subject: Re: panic from _mutex_assert in kern_lock.c In-Reply-To: "from Robert Watson at Oct 5, 2002 01:30:36 pm" To: Robert Watson Date: Sat, 5 Oct 2002 10:49:26 -0700 (PDT) Cc: "Brian F. Feldman" , freebsd-current@freebsd.org, kirk@freebsd.org X-Mailer: ELM [version 2.4ME+ PL88 (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Robert Watson said: > > On Sat, 5 Oct 2002, Steven G. Kargl wrote: > > > One other point, the machine was doing a background fsck on /var. Does > > a background fsck go through ffs_snapshot()? > > Yes -- the background file system checker creates a snapshot of the file > system in the un-checked state, then performs the check against the > snapshot. It trickles the changes generated against the snapshot into the > live file system. Because of the conservative nature of failures with > soft updates, the only theoretical inconsistencies relate either to marked > as non-free yet unreferenced resources, and referenece counts that are > high. The snapshot allows fsck a consistent view of the file system "as > it was" so that it doesn't get confused by the live file system. > Thanks, Brian and Robert. Of course, the above makes sense when someone explains it to you. -- Steve http://troutmask.apl.washington.edu/~kargl/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message