From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ipmail05.adl6.internode.on.net ([150.101.137.143]:5530 "EHLO ipmail05.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751348AbbHQAE3 (ORCPT ); Sun, 16 Aug 2015 20:04:29 -0400 Date: Mon, 17 Aug 2015 10:03:36 +1000 From: Dave Chinner Subject: Re: [PATCH] generic/084: check inotify limit before tail many files Message-ID: <20150817000336.GE20596@dastard> References: <1439482592-29611-1-git-send-email-zlang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1439482592-29611-1-git-send-email-zlang@redhat.com> Sender: fstests-owner@vger.kernel.org To: Zorro Lang Cc: fstests@vger.kernel.org, eguan@redhat.com List-ID: On Fri, Aug 14, 2015 at 12:16:32AM +0800, Zorro Lang wrote: > generic/084 try to run 'tail' command, tail will use > inotify, and there're some limit about inotify. I think > the most important is fs.inotify.max_user_instances, then > fs.inotify.max_user_watches is importand too. > > When I test on a machine with 154 cpu cores, this case > run failed, and hit many warning likes: > > tail: inotify cannot be used, reverting to polling: Too many > open files > > Because the fs.inotify.max_user_instances is 128, so if > we try to tail 154 files, it will be failed. We use 'tail' all over the place in xfstests, so why is only generic/084 affected? And really, this seems more like a distro/environment bug and doesn't need xfstests help to work around. i.e. changing the sysctl before starting xfstests seems much more appropriate than hacking it a random test. Especially as there may be more than one test that is affected by this, and when run in a random order this would cause those other tests to pass/fail depending on whether generic/084 had already been run on that machine.... Cheers, Dave. -- Dave Chinner david@fromorbit.com