From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.74) (envelope-from ) id 1QCFDn-0006Ls-I1 for ltp-list@lists.sourceforge.net; Tue, 19 Apr 2011 18:00:19 +0000 Received: from mx4-phx2.redhat.com ([209.132.183.25]) by sog-mx-1.v43.ch3.sourceforge.com with esmtp (Exim 4.74) id 1QCFDm-0002vQ-74 for ltp-list@lists.sourceforge.net; Tue, 19 Apr 2011 18:00:19 +0000 Date: Tue, 19 Apr 2011 14:00:11 -0400 (EDT) From: Jan Stancek Message-ID: <1460652483.36832.1303236011908.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com> In-Reply-To: MIME-Version: 1.0 Subject: Re: [LTP] [PATCH] cgroups/cgroup_regression_test: fix sporadic failures List-Id: Linux Test Project General Discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-list-bounces@lists.sourceforge.net To: Garrett Cooper Cc: ltp-list@lists.sourceforge.net ----- Original Message ----- > From: "Garrett Cooper" > To: "Jan Stancek" > Cc: ltp-list@lists.sourceforge.net > Sent: Tuesday, April 19, 2011 7:40:46 PM > Subject: Re: [LTP] [PATCH] cgroups/cgroup_regression_test: fix sporadic failures > On Tue, Apr 19, 2011 at 9:31 AM, Jan Stancek > wrote: > > > > > > ----- Original Message ----- > >> From: "Garrett Cooper" > >> To: "Jan Stancek" > >> Cc: ltp-list@lists.sourceforge.net > >> Sent: Tuesday, April 19, 2011 6:13:48 PM > >> Subject: Re: [LTP] [PATCH] cgroups/cgroup_regression_test: fix > >> sporadic failures > >> On Tue, Apr 19, 2011 at 6:27 AM, Jan Stancek > >> wrote: > >> > > >> > There were failures caused by incomplete cleanup, > >> > leaving groups behind after some stress tests. > >> > Some stress tests failed to complete upon receiving SIGUSR1. > >> > > >> > 1. dmesg can rotate and number of found bugs can actually go down > >> > clear the buffer before test to avoid this > >> > > >> > 2. test_5: test should mount 2 subsystems, but mount command > >> > says "$subsys" instead of "$subsys2" > >> > > >> > 3. test_6: test may leave groups behind, fix rmdir > >> > to match test_6_1.sh > >> > > >> > 4. test_7_2: mounts whole cgroup not $subsys > >> > > >> > 5. test_10: can leave cgroups umounted before cleanup > >> > make sure cgroups are mounted before doing cleanup > >> > > >> > 6. test_*.sh scripts use trap in loop, which may cause bash > >> > to miss signal, see > >> > https://bugzilla.redhat.com/show_bug.cgi?id=695656 > >> > move trap outside loop to avoid it > >> > >> I personally don't have a lot of context into cgroups, but when is > >> it acceptable for Linux to send SIGUSR1 when mounting, unmounting, > >> or > >> removing cgroup directories? > > > > The main test spawns couple of workers, which run infinite loop and > > stress > > test some area. SIGUSR1 was chosen by author of test to stop these > > workers > > after certain amount of time. > > > > The signal only controls workers, it is not directly related to any > > cgroup functionality AFAIK. > > > > Unfortunetly, when resetting "trap" in bash, signal is ignored for > > short period of time, which occasionally hangs the whole test. > > That just sounds like a cop-out for fixing a bug in bash. Unless > the item is documented in bash and/or the POSIX spec prior to that > bug, I would just push back on the devs until they fix the shell. > Setting signal handlers in a synchronous fashion isn't rocket science. > Thanks, > -Garrett I am trying to push them :-). If you look at bz, maintainer is trying to get things moving upstream: http://www.mail-archive.com/bug-bash@gnu.org/msg09099.html But at the same time, it seems pointless for test to keep resetting signal handler in busy loop, unless it is a bash stress test. One way or another, bash folks will deal with the issue: fix it or document it. Avoiding this problem by moving trap out of loop allows people to use test also on older versions. Or as alternative, I can put in extra "kill -SIGTERM", so even when SIGUSR1 gets lost, test will be able to progress. ------------------------------------------------------------------------------ Benefiting from Server Virtualization: Beyond Initial Workload Consolidation -- Increasing the use of server virtualization is a top priority.Virtualization can reduce costs, simplify management, and improve application availability and disaster protection. Learn more about boosting the value of server virtualization. http://p.sf.net/sfu/vmware-sfdev2dev _______________________________________________ Ltp-list mailing list Ltp-list@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/ltp-list