From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org ([80.91.229.3]:58805 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753375Ab3JYNld (ORCPT ); Fri, 25 Oct 2013 09:41:33 -0400 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1VZhdr-0006PU-JR for linux-btrfs@vger.kernel.org; Fri, 25 Oct 2013 15:41:32 +0200 Received: from 63-245-179-205.ip.mtelco.net ([63-245-179-205.ip.mtelco.net]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 25 Oct 2013 15:41:31 +0200 Received: from jgoerzen by 63-245-179-205.ip.mtelco.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 25 Oct 2013 15:41:31 +0200 To: linux-btrfs@vger.kernel.org From: John Goerzen Subject: rm with quotas can cause panic (was Re: Lots of trouble hanging when rm files with many extents) Date: Fri, 25 Oct 2013 13:41:11 +0000 (UTC) Message-ID: References: <20131020235118.3a918ba3@virtall.com> <5264A221.2020509@complete.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-btrfs-owner@vger.kernel.org List-ID: John Goerzen complete.org> writes: > > On 10/20/2013 09:51 AM, Tomasz Chmielewski wrote: > > I'll do some more tests with lots of extents to see if it's > > reproducible here as well. > > > > > Interestingly, I've generally had qgroups enabled here as well, possibly > on all of these systems. Could that be the culprit? Updating the subject here, because it seems increasingly likely that quotas are the problem causing OOM panics. I was able to reproduce the problem on a test filesystem with quotas enabled. After quotas were disabled and the system was rebooted, the problem no longer occurred. The dangerous combination seems to be many extents plus quotas. Sadly, quotas are the only way to have btrfs keep track of how much space subvols are using, so it's very useful to be able to use that feature. I also noted this at https://bugzilla.kernel.org/show_bug.cgi?id=63071 John