okay to disable lvm? reduces boot delay from dvd drives

[Phil Dybvig]

Hi!  I recently had a big slow-down in boot time.  At first I assumed it was one 
of the updates, but I am pretty sure now it was due to lvm and the fact that I 
left music/vcds in the dvd drives.  The delay was between mounting the root 
partition and the swap space; looking at /etc/rc.d/rc.sysinit I figured it was 
due to lvm (logical volume management), whatever that is.  In var/log/messages, 
there were errors from the cd drives, sometimes few (2 each) and sometimes many 
(corresponding to long delays in booting, so long that at first I always assumed 
it was hung and did a hard reboot).  Setting up verbose logging for lvm yielded 
``no volume groups found'' so i figured it wasn't doing anything and I disabled 
it by renaming /sbin/lvm.static to /sbin/lvm.static.bk.  Then booting has been 
fast and the /dev/hda and /dev/hdb errors from the cd drives disappeared.

All of this is good so far, but I want to ask to make sure that lvm isn't 
something I will need later and do not want to disable.  Also, out of curiosity, 
what is lvm and when is it needed?  The references to lvm on this list only say 
that if you use lvm, you should not even think about using yum or apt to upgrade 
from FC1 to FC2.