From owner-freebsd-fs@FreeBSD.ORG Wed May 3 10:04:03 2006 Return-Path: X-Original-To: freebsd-fs@freebsd.org Delivered-To: freebsd-fs@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 73EAA16A403 for ; Wed, 3 May 2006 10:04:03 +0000 (UTC) (envelope-from freebsd-fs@merdin.com) Received: from smtp.mailix.net (smtp.mailix.net [216.148.213.132]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1092443D46 for ; Wed, 3 May 2006 10:04:02 +0000 (GMT) (envelope-from freebsd-fs@merdin.com) Received: from [62.148.144.242] (helo=[62.148.144.242]) by smtp.mailix.net with asmtp (Exim 4.24-H) id 1FbEDI-0000ed-Ov for freebsd-fs@freebsd.org; Wed, 03 May 2006 03:04:09 -0700 Date: Wed, 3 May 2006 14:03:55 +0400 From: Pavel Merdine X-Mailer: The Bat! (v3.71.04) Professional X-Priority: 3 (Normal) Message-ID: <213965528.20060503140355@merdin.com> To: Kris Kennaway In-Reply-To: <20060502221306.GD95348@xor.obsecurity.org> References: <20060502193900.GA94069@peter.osted.lan> <1541458526.20060503003229@merdin.com> <20060502221306.GD95348@xor.obsecurity.org> MIME-Version: 1.0 X-SA-Exim-Mail-From: freebsd-fs@merdin.com Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-SA-Exim-Version: 3.1 (built Thu Oct 23 13:26:47 PDT 2003) X-SA-Exim-Scanned: No; Unknown failure X-uvscan-result: clean (1FbEDI-0000ed-Ov) Subject: Re[2]: Stress testing the UFS2 filesystem X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 May 2006 10:04:03 -0000 Hello , Wednesday, May 3, 2006, 2:13:07 AM, you wrote: > On Wed, May 03, 2006 at 12:32:29AM +0400, Pavel Merdine wrote: >> Hello , >> >> Thank you for raising this problem again. I already tried to do that >> in that list, but received an answer that kernel is intended to do >> that. For example, you have a faulty disk. And you have a faulty >> sector which happened to occur on the directory place. So each time >> kernel reads this sector it panics. So it's initially hard to even >> understand what happens. And also it leads to corruption and lost >> files on other file system (each time). Imagine if you have 15 disks. >> In this case you have many files lost just because of a small (and not >> significant) fault. It's just a nonsense. >> Personally, I just replaced bad_dir with error return. >> By the way, there was some bug in fs in kernel that could lead to >> panic even on clean filesystem (bad_dir as far as I remember). It is >> very rare and it was fixed on DragonFly. As far as I remember a fix >> for this was also commited to current recently. >> >> I think that Linux is usually much smarter on this. By default it >> remounts a file system as read-only in case it detects a filesystem >> corruption. I would be very happy if FreeBSD could do the same, >> because fs panics really hurt when you have many systems with disks. >> >> Of course I think we could do patches to overcome corrupting panics, >> but the core FreeBSD team would not accept this, as they are happy >> with panics and corruptions they make to other filesystems. > Of course not, don't make silly accusations :-) > The problem is much more difficult to solve than "making the panic an > error return". I think that is you who call me silly. I did not mean what you wrote. Where did I say that? I just said I made an error return for myself. And it was a quick patch to stop infinite series of panics (leaded to hundred files lost). What would you do in that case, very smart and genius man? I wrote I would be very happy if FreeBSD could do read-only remounts. > Kris -- / Pavel Merdine