Subject: Re: overfilling mfs partitions larger than 600M causes kernel panics
To: Tim Kelly <hockey@dialectronics.com>
From: Hernani Marques Madeira <hernani@vecirex.net>
List: port-macppc
Date: 11/18/2004 17:08:42
On Thu, Nov 18, 2004 at 09:50:14AM -0500, Tim Kelly wrote:

> I want to bring this up again. I only got one confirmation from a macppc
> user, and one deny from a i386 user.

I tested it using hpcarm and running
2.0_RC4 NetBSD 2.0_RC4 
from
Tue Nov  9 22:36:35 CET 2004 (sources got earlier on that day).

1. attempt with 600 megs:
[snip]
 mkdir /mfs
 mount_mfs -s 600m ffs /mfs
UVM: pid 502 (mount_mfs), uid 0 killed: out of swap
killed
[/snip]
-> nothing mounted at /mfs

2. attempt with 300 megs:
[snip]
 mount_mfs -s 300m ffs /mfs
[/snip]
-> system hangs completely (without any output)

3. attempt (after booting up again) with 300 megs:
[snip]
 mount_mfs -s 300m ffs /mfs
 mount -t mfs
mfs:316 on /tmp type mfs (synchronous, local)
mfs:338 on /mfs type mfs (synchronous, local)
 df -h /mfs
Filesystem    Size     Used     Avail Capacity  Mounted on
mfs:338       291M     1.0K      276M     0%    /mfs
cp -R /usr/* /mfs
[/snip]
-> system hangs completely (without any output)

4. attempt (after booting up again) with 32 megs (as much as the system has)
[snip]
 mount_mfs -s 32m ffs /mfs
 cp -R /usr/* /mfs
[/snip]
-> system hangs completely (without any output)

5. attempt (after booting up again) with 16 megs (the system has 15M free
   after what top(1) says) 
[snip]
 mount_mfs -s 16m ffs /mfs
 cp -R /usr/* /mfs
cp: /mfs/sbin/rpcbind: Cannot allocate memory
[/snip]
-> system hangs completely

6. attempt (after booting up again) with 8 megs (15M free)
[snip]
 mount_mfs -s 8m ffs /mfs
 cp -R /usr/* /mfs
# ... messages that filesystem /mfs is full and that's no space left ...
 df -h /mfs
Filesystem	Size	Used	Avail Capacity	Mounted on
mfs:493		7.5M	7.5M	-381K	105%	/mfs
[/snip]
-> system continues to work properly

-- 
hernani