[Swlug] lvm - moving data

[bascule]

if i have two physical disks in the same logical volume is it possible to have 
the data move from one of them to the other in the background, pausing when i 
turn my machine off and starting when i turn on again.
i ask because i have a 2tb drive in my machine as /home and i wish to add 
another 2 tb drive and use that as /home instead, since copying 2tb can take a 
while i wondered if i could have it done in the background while i still use 
the computer, both drives are fine so this isn't a rescue operation, the newer 
drive i have acquired is simply just that, newer with a much lower power up 
time

bascule