From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Leslie Rhorer" Subject: RE: RAID halting Date: Thu, 9 Apr 2009 23:51:41 -0500 Message-ID: <20090410045146.TNPB12747.cdptpa-omta01.mail.rr.com@Leslie> References: <20090410030252.RSAN6222.cdptpa-omta03.mail.rr.com@Leslie> Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090410030252.RSAN6222.cdptpa-omta03.mail.rr.com@Leslie> Sender: linux-raid-owner@vger.kernel.org To: 'Linux RAID' List-Id: linux-raid.ids > > for f in /sys/block/*/queue/scheduler; do > > echo noop > $f > > echo $f "$(cat $f)" > > done > > OK, I did this. Two questions: It doesn't seem to have helped or hindered. I still get halts, but under moderate loads not every time. > > Leslie: I still think finding out what the kernel is doing during the > > stall would be a HUGE hint to the problem. Did you look into oprofile or > > ftrace? > > I couldn't find a Debian source for ftrace, but I did download oprofile. Something very disturbing is happening now, however. Just a few minutes after loading oprofile, the system did a sudden total shutdown. The file systems were all left dirty, and power was suddenly cut to the main chassis. This has never happened before. I rebooted the system, and the file systems replayed their journals. Some data was lost, of course, but nothing serious. A few hours later, the exact same thing happened again: A sudden shut-down. Nothing like this has ever happened before. Of course the system can issue a power shutdown from software, but it is supposed to clean up the file systems first, and it's not supposed to just do it autonomously.