Message-ID: <010601c1a9e0$f4210e20$47426682@csee.uq.edu.au>
From: "Chris Pascoe" <c.pascoe@itee.uq.edu.au>
To: "Stephen Lord" <lord@sgi.com>
Cc: <linux-xfs@oss.sgi.com>
References: <023501c1a953$f059a0f0$47426682@csee.uq.edu.au> <3C57F97A.7000400@sgi.com>
Subject: Re: How long should an xfs_freeze take?
Date: Thu, 31 Jan 2002 08:51:50 +1000
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> How long freeze takes depends on how much data is dirty in the
> filesystem, it should take a similar time to an unmount. However,
> unless this was a very large and dirty filesystem this feels
> like a long time - although it was all system time,
> so something was going on.

6 hours is a long time for an unmount!  The volume is ~70GB, and had no
activity on it before I tried to create the snapshots - the machine had just
been rebooted before some attempts.

> The spot you kept seeing on the stack does not make much sense, vn_count
is
> basically an atomic_read.

It just seems that's the place I've hit the break key the most.  A closer
examination of my console log suggests it isn't stuck in vn_count, there are
a few occurances of it being somewhere else in xfs_iflush_all - so maybe
it's got itself tangled in a loop for a few hours?

0xe95c3b88 0xc01a1a63 xfs_iflush_all+0xc3
                        (0xf6d1f000, 0x1, 0xf6d1f000, 0xc, 0xc039ce80)
0xe95c3b88 0xc01a1ab9 xfs_iflush_all+0x119
                        (0xf6d1f000, 0x1, 0xf6d1f000, 0xc, 0xc039ce80)
0xe95c3b88 0xc01a1ac3 xfs_iflush_all+0x123
                        (0xf6d1f000, 0x1, 0xf6d1f000, 0xc, 0xc039ce80)

> 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.

Chris