Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 3 Feb 2003 10:00:23 -0500 (EST)
From:      Robert Watson <rwatson@freebsd.org>
To:        Jaye Mathisen <mrcpu@internetcds.com>
Cc:        current@freebsd.org
Subject:   Re: How to freeze up your FreeBSD 5.0 box.
Message-ID:  <Pine.NEB.3.96L.1030203095606.63806S-100000@fledge.watson.org>
In-Reply-To: <20030203074936.GA74854@backmaster.cdsnet.net>

next in thread | previous in thread | raw e-mail | index | archive | help
Jaye,

Thanks for the report.  Haven't seen it here, but I also don't have a
configuration that looks like that one.  In order to usefully debug this,
we'll need some more information -- off the top of my head, it sounds a
lot like a file system pseudo-deadlock of some sort.  Perhaps a race to
the root due to locking during a long operation.  If you could compile
your kernel with "options DDB", assuming it's not already, and set up a
serial console, that would be helpful.  When you reproduce the apparent
hang, break into ddb on the console, and send the output of the following
two commands:

	show lockedvnods
	ps

You don't strictly have to use a serial console, but it sure is a lot
easier to copy/paste the output than to copy by hand.  You can find
detailed instructions for setting this up in the Handbook and Developer's
Handbook.

A few things to tickle the thinking process: is the hang immediate, or
does it wait until something else lists one of those directories?  Does
the hang occur if you perform the same behavior locally, or only over NFS?
Do the disks churn during the deletion, or does it seem to be a
CPU-intensive activity?  Suppose you stick all these files a few levels
fdown in the directory hierarchy -- does it help?

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Network Associates Laboratories

On Sun, 2 Feb 2003, Jaye Mathisen wrote:

> 
> 
> THis is repeatable for me at will.
> 
> 5.0-current, supped as of 2/1.
> 
> 4 80GIG maxtors on 2 promise IDE ultra 66 cards, exported via NFS.
> 
> 
> newfs'd an 80G FS on each drive, created one big file filled with
> zero's from /dev/zero on each drive. (Softupdates/UFS1)
> 
> login to my other box, which has the 4 drives mounted via NFS
> (the other box being 4.7-stable as of 1/28/03).  options
> from fstab are bg,intr,rw, don't recall if it was v2 or v3 NFS,
> although mountd was started with defaults, so I'm assuming v3.
> 
> do (on the 4.7-stable box):
> 
> rm /mntpt1/bigfile & 
> rm /mntpt2/bigfile &
> rm /mntpt3/bigfile &
> rm /mntpt4/bigfile &
> 
> 
> And then switch back to the 5.0 current box, only to find out
> that it will not respond to any network traffic via ssh.  Will
> respond to pings.  
> 
> I can type my login/pw on the console, but hitting return
> after typing my pw just sits there, until I ran out of VTY's.
> 
> df on the 4.7 box hangs.
> 
> AFter about 30 minutes, when the files finally finished being deleted,
> control of 5.0 box was returned, and everything was back and functioning
> properly.
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-current" in the body of the message
> 


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.NEB.3.96L.1030203095606.63806S-100000>