Date: Fri, 1 Feb 2002 08:04:32 +1000 (EST)
From: Chris Pascoe <c.pascoe@itee.uq.edu.au>
To: linux-xfs@oss.sgi.com
Subject: Re: How long should an xfs_freeze take?
Message-ID: <Pine.GSO.4.40.0202010758001.27162-100000@mango.csee.uq.edu.au>
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Hi Steve,

> > How repeatable is this?
> >
> > The problem was persistent across reboots - I rebooted to install a
> > different LVM version at some stage (move to 1.0.2, from 1.0.1), and it
> > occurred five times in a row after that.  I just rebooted now to say
that it
> > still happens - but, alas - it doesn't want to any more.  I'll try again
at
> > some random times throughout the day.

I can repeat this fairly reliably now - do a meaningless rsync across the
disk (i.e. rsync itself to itself - makes it stat every file on the disk, I
guess), then try an xfs_freeze after the rsync completes:

rsync -aH /tst1/ /tst1/
time xfs_freeze -f /tst1

It's been hung there for ~10 minutes now, I've repeated this twice....
rebooting - will try again...  This time it doesn't want to do it.. :(

This time I've done a rsync with real data:

testbox# time rsync -e ssh -avH --stats root@fs:/home/01/ /tst1/ ; time xfs_freeze -f /tst1  ; time xfs_freeze -u /tst1

Number of files: 602545
Number of files transferred: 292
Total file size: 62690390294 bytes
Total transferred file size: 1728372390 bytes
Literal data: 177119547 bytes
Matched data: 1551577350 bytes
File list size: 15575582
Total bytes written: 4690480
Total bytes read: 195767044

wrote 4690480 bytes  read 195767044 bytes  100808.41 bytes/sec
total size is 62690390294  speedup is 312.74

real    33m7.243s
user    1m34.200s
sys     2m8.250s

I'm sitting waiting for the xfs_freeze again - so I can replicate
the problem, yes.  It takes at least 40 minutes to complete xfs_freeze's
after this point (i.e. you can go xfs_freeze -f ; xfs_freeze -u ;
xfs_freeze -f ; xfs_freeze -u, and the second freeze still takes
forever!), during which time the machine is completely unresponsive.

Chris