From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: [RFC] online scrub for ext4 Date: Fri, 21 Jul 2017 17:26:43 -0700 Message-ID: <20170722002643.GD4211@magnolia> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4 To: "Theodore Ts'o" Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:49986 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751464AbdGVA0s (ORCPT ); Fri, 21 Jul 2017 20:26:48 -0400 Content-Disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi all, On this week's conference call, we discussed polishing e2croncheck into something resembling a workable package, and I mentioned that some time ago I'd adapted the script into a more general utility. I've cleaned up the scripts somewhat, so we can use them as a basis for discussion. The first mail contains the base script to create the lvm snapshot, fsck the snapshot, remove the snapshot, and fstrim the original filesystem. It also contains a udev script to discourage it from making symlinks in /dev/disk. The second mail contains a script to identify eligible lvs containing ext4 filesystms and call the actual invoker script. The third mail contains systemd units to manage invocation and containment of the scripts. Note that despite my earlier outline, I don't actually have a boot time script that cleans out any leftover fsck snapshots, though it wouldn't be difficult to write. Note also the lack of distro installer/partitioner support -- your ext4 filesystems /must/ be managed by lvm, and you /must/ have at least 256M free in each volume group. There's no daemon to watch for snapshots filling up in order to kill the fsck and snapshot. --D