Re: Software RAID efficiency: Disks vs partitions

Hi,

Did some tests between various scenarios: RAID-10/RAID-6
with three 3TB disks, and RAID-6 with 12 1TB partitions, using:
  dd if=/dev/zero of=/mnt/md1/out.txt bs=64k count=32000 conv=fdatasync

RAID-10 with disks was obviously the best (2x write speed),
RAID-6 with disks gave 1X, but surprisingly RAID-6 with partitions
was still at 0.8x, even with the RAID in active sync, and with the
partitions not optimally aligned in order to ensure that they are
exactly the same. If this is the case, I am willing to live with that
much loss in speed.

Read speeds are always the same, but that is probably because of
OS/disk caching, and I need to fix my scripts.

Regards,
Gora