deadlock or bad disk ? RELENG_8

[Sascha Holzleiter]

> 
> just hangs, I guess because its having trouble reading from the disk.
> If I hit CTRL+t, I see
> 
> load: 0.00  cmd: csh 73167 [vnread] 22.32r 0.00u 0.00s 0% 3232k
> load: 0.00  cmd: csh 73167 [vnread] 22.65r 0.00u 0.00s 0% 3232k
> load: 0.00  cmd: csh 73167 [vnread] 22.96r 0.00u 0.00s 0% 3232k
> load: 0.00  cmd: csh 73167 [vnread] 23.20r 0.00u 0.00s 0% 3232k
> load: 0.00  cmd: csh 73167 [vnread] 23.40r 0.00u 0.00s 0% 3232k
> load: 0.00  cmd: csh 73167 [vnread] 23.61r 0.00u 0.00s 0% 3232k
> 
> 

Hi,

i have similar problems on a i7 system with a 3ware 9650SE controller and a 
simple 2 disk RAID1 configuration. I can trigger it by just extracting the 
ports tree onto the raid. It usually stops several times for over a minute 
doing nothing before continuing.  While building KDE it stopped for good when 
extracting a port. The bsdtar process was hanging there in the wdrain status. 
Waited over 60 minutes before interrupting the process.
I haven't seen any messages in dmesg. I'll try to build with debug support 
tonight and see if it makes a difference. The version was the one delivered 
with the PC-BSD 8.1RC discs but also after upgrading to the newest RELENG_8 
sources the problem persists. The hardware is fairly new and other OSes show 
no problems so i'm inclined to say that the hardware isn't faulty ;)
I could also try to install a 8.0 system if it helps to determine if a 
regression in 8.1 is the problem.