I'm going to install a CentOS6 Server with Virtualization ( libvirtd ) capabilities on a DELL Server with Hardware RAID5 of around 6T of disk space ( It has 4x2T disks in a PERC700 RAID Controller ).

I'm going then to install some guests which requires few resources except one that needs 500GB of disk space, 8/16GB of RAM and good performances. I was thinking about file images for guests storage but I'm not sure about the 500GB VM what needs good performances so that an LVM device could be better.

So my question is what would be the best layout concerning:

1. RAID setup ( RAID5, RAID1 + 1 disk for OS only. )
2. disk partitioning ( using the entire disk/ leave free space for future use and extending it with LVM )
3. guests storage management ( LVM devices or file images ( considering the 500GB VM that is performance demanding ) or mixed )
4. Where to put guests storage? /var/lib/libvirt/images or maybe in a custom dir separated from system /home/VMs

Thanks in advance for any hint.