From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from csamuel.org ([74.50.50.137]:51151 "EHLO csamuel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752443AbaHXMt4 (ORCPT ); Sun, 24 Aug 2014 08:49:56 -0400 Received: from localhost (localhost [127.0.0.1]) by csamuel.org (Postfix) with ESMTP id 898E7405C7 for ; Sun, 24 Aug 2014 22:49:55 +1000 (EST) Received: from csamuel.org ([127.0.0.1]) by localhost (csamuel.org [127.0.0.1]) (amavisd-maia, port 10024) with LMTP id 01810-05 for ; Sun, 24 Aug 2014 22:49:55 +1000 (EST) Received: from quad.localnet (2001-44b8-41dd-d500-5c25-1b76-13ce-24c4.static.ipv6.internode.on.net [IPv6:2001:44b8:41dd:d500:5c25:1b76:13ce:24c4]) by csamuel.org (Postfix) with ESMTPSA id 17FF5405C4 for ; Sun, 24 Aug 2014 22:49:55 +1000 (EST) From: Chris Samuel To: linux-btrfs@vger.kernel.org Subject: Re: superblock checksum mismatch after crash, cannot mount Date: Sun, 24 Aug 2014 22:49:51 +1000 Message-ID: <2850101.SbkCu8D9cB@quad> In-Reply-To: <20140824110853.GB22693@apia.perrit.net> References: <53F7BD8E.10308@floga.de> <20140824110853.GB22693@apia.perrit.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Sun, 24 Aug 2014 01:08:53 PM Leen Besselink wrote: > tip for basically any Linux filesystem, especially on Flash-based storage > and also btrfs: - use noatime (if you aren't doing that already, don't know > if that is the default in btrfs) Since 2.6.30 (5 years old now) the kernel has defaulted to mounting filesystems with relatime not atime so it's not as bad as it used to be. This is from the mount manual page. relatime Update inode access times relative to modify or change time. Access time is only updated if the previous access time was earlier than the current modify or change time. (Similar to noatime, but doesn't break mutt or other applications that need to know if a file has been read since the last time it was modified.) Since Linux 2.6.30, the kernel defaults to the behavior provided by this option (unless noatime was specified), and the strictatime option is required to obtain traditional semantics. In addition, since Linux 2.6.30, the file's last access time is always updated if it is more than 1 day old. All the best, Chris -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC