From: tytso@mit.edu Subject: Re: [PATCH] default max mount count to unused Date: Thu, 21 Jan 2010 20:29:29 -0500 Message-ID: <20100122012929.GA21263@thunk.org> References: <4B5785A5.2010505@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: ext4 development , Bill Nottingham To: Eric Sandeen Return-path: Received: from THUNK.ORG ([69.25.196.29]:40014 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755709Ab0AVB3j (ORCPT ); Thu, 21 Jan 2010 20:29:39 -0500 Content-Disposition: inline In-Reply-To: <4B5785A5.2010505@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, Jan 20, 2010 at 04:37:25PM -0600, Eric Sandeen wrote: > From: Bill Nottingham > > Anaconda has been setting the max mount count on the root fs > to -1 (unused) for ages. > > I (Eric) tend to agree that using mount count as a proxy for potential > for corruption seems odd. And waiting for fsck on a reboot just because > it's number 20 (or so) is painful. Can we just turn it off by default? > > I wouldn't mind killing the periodic check as well, but consider > this a trial balloon. :) I think it would be better to make this be something tunable via mke2fs.conf. And as a profile option, maybe we would want this to be something where we periodically force a full fsck check and then send TRIM commands down to the SSD. Given the size and speed of SSD's, doing periodic TRIM's every N mounts mike actually be a good thing. (It's dangerous to do a TRIM without doing a full fsck since if the block allocation bitmap isn't quite right, the user could lose data.) - Ted