On 21.01.2012 11:49, Martin Steigerwald wrote:

Am Dienstag, 20. Dezember 2011 schrieb Martin Steigerwald:

When I do btrfs scrub start / the machine locks immediately up hard.

Can you please give me the output of sysrq-w when the machine is locked up?

Thanks,
Arne

Then usually on next boot it stops on space_cache enabled message, but not 
the one for /, but the one for /home which is mounted later.

When I then boot with 3.1 it works. BTRFS redos the space_cache then while 
the machine takes ages to boot - I mean ages - 10 minutes till KDM prompt 
is no problem there.

I thought I just mention it here.

Since I got no hints on what to do, I probably redo both filesystems on the 
machine. Should that not work out, I switch the box to Ext4.

btrfs filesystem scrub works on my ThinkPad T520 with 64-bit debian and 
Intel SSD 320 and one 2,5 inch external drive as well as a 3,5 inch 
external backup drive both via eSATA, so this seems to be no principal 
issue. It also works on a workstation at work which has 32-bit debian as 
well.

Thanks,