Hallo, Andreas,

Du meintest am 20.01.11:

Maybe it is a very stupid question but I want to ask it anyway. In
general, 'btrfs filesystem balance' takes very long to finish and
produces lots of IO. So what are the classical usage scenarios, when
it is (really) worth doing a balance?

Here (Kernel 2.6.37, btrfs git Nov. 2010): balancing two disks/ 
partitions with 2 and 1.5 TByte needs about 24 hours (CPU 1.5 GHz).

What do you mean with "lots of IO"? the messages in "/var/log/messages"  
and "/var/log/warn"?

Viele Gruesse!
Helmut