From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([69.77.167.62] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1LdmTl-0007QT-8k for garchives@archives.gentoo.org; Sun, 01 Mar 2009 14:17:17 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 13F99E0234; Sun, 1 Mar 2009 14:17:14 +0000 (UTC) Received: from smtp.cs.nyu.edu (SMTP.CS.NYU.EDU [128.122.80.33]) by pigeon.gentoo.org (Postfix) with ESMTP id E310CE0234 for ; Sun, 1 Mar 2009 14:17:13 +0000 (UTC) Received: from ajglap.localdomain (ool-4578da1c.dyn.optonline.net [69.120.218.28]) (authenticated bits=0) by smtp.cs.nyu.edu (8.14.3/8.13.8) with ESMTP id n21EHCYP014075 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Sun, 1 Mar 2009 09:17:13 -0500 (EST) Received: by ajglap.localdomain (Postfix, from userid 1502) id 2FDFC19D922; Sun, 1 Mar 2009 09:17:06 -0500 (EST) From: Allan Gottlieb To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Re: A little light relief from endless problems References: <200903011147.09719.peter@humphrey.ukfsn.org> Date: Sun, 01 Mar 2009 09:17:05 -0500 In-Reply-To: (Nikos Chantziaras's message of "Sun, 01 Mar 2009 13:57:30 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.91 (gnu/linux) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Archives-Salt: a6486db2-7d25-4a09-b795-a63d1bdf7b4b X-Archives-Hash: 415823d74806764d714757a2a7d26920 At Sun, 01 Mar 2009 13:57:30 +0200 Nikos Chantziaras wrote: > Peter Humphrey wrote: >> As it's Sunday, here's an odd little thing. >> >> Not long ago, while booting this machine, four ext3 partitions >> needed checks on remount count reaching zero. They had been set to >> 23, 24, 25 and 26 mounts. (I didn't choose the numbers; they were >> allocated at the time I was creating the file system.) >> >> Now, this box does get rebooted, but hardly 23 x 24 x 25 x 26 = >> 358,800 times all told. At, say, two reboots per day, that would >> take rather a long time: a little under 500 years if my arithmetic >> is working. > > I think you're confused. 23 means a check each 23 mounts. With 2 > mounts per day, that's a check every 12 days for the first and second > disk. I think the point is that 23, 24, 25, 26 are relatively prime so that, if N is initially zero, it takes 23x24x25x26 increments initially for (N mod 23), ..., (N mod 26) to all again be zero. > Also, except mount count, there's also a time-based check. The check > happens whichever of the two expires first (otherwise, a system that > gets rebooted once each two months or such would get checked in a > timely manner.) This second point is quite valid. allan