dangerous situation with shutdown process

[Bill Vermillion]

On Thu, Jul 14, 2005 at 22:31 , freebsd-stable-request at freebsd.org
moved his mouse, rebooted for the change to take effect, and then
said:


> Message: 13
> Date: Thu, 14 Jul 2005 20:38:15 +0200
> From: Anatoliy Dmytriyev <tolid at plab.ku.dk>
> Subject: dangerous situation with shutdown process
> To: freebsd-stable at freebsd.org, freebsd-questions at freebsd.org
> Message-ID: <42D6B117.5080302 at plab.ku.dk>
> Content-Type: text/plain; charset=UTF-8; format=flowed

> Hello, everybody!

> I have found unusual and dangerous situation with shutdown process:
> I did a copy of 200 GB data on the 870 GB partition (softupdates is 
> enabled) by cp command.

> It took a lot of time when I did umount for this partition
> exactly after cp, but procedure finished correctly.

> In case, if I did ???shutdown ???h(r)???, also exactly after cp,
> the shutdown procedure waited for ???sync??? (umounting of the
> file system) but sync process was terminated by timeout, and
> fsck checked and did correction of the file system after boot.

> System 5.4-stable, RAM 4GB, processor P-IV 3GHz.

> How can I fix it on my system?

Copying very large files and then shutting down I hope is not a
normal procecure for you.   softupdates sometimes do take a long
time when you are removing/copying very large files.

Others have suggested different time-outs but you'd have to figure
out the largest size you may every encounter and set things for
that, which is not going to help for everyday operation.

I've watched the amount of disk space increase slowly by performing
'df' and it can take a long time - up to a minute on some extremely
large partitions I was cleaning.

One way to force everything to be written I've found [by
observation only] is to perform an fsck on that file system.

If you only do huge copies and immediate shutdowns rarely, then
maybe it's just a good idea to remember how softupdates work, and
then fsck, then shutdown.

I'm always against changing default operations from typical 
operations to extremes.

Bill
-- 
Bill Vermillion - bv @ wjv . com