I have a machine with three, fifteen drive mdraid RAID-6 arrays (md10, md20, md30.) These three arrays are then setup as physical volumes for LVM and combined into a single volume group.
I then have been creating logical volumes from the VG using the following command:
lvcreate -i 3 -I 4 -L 10T -n
These volumes are then being served out as block devices via FCoE.
My question is if I need to do anything with the chunk/stripe sizes to make this work as well as it should? If I have 15 drive, RAID-6 arrays, does the stripe size that LVM passes down to the RAID device need to be 13x the size of the RAID chunk size (since I have double parity) so that I can actually get the full speed of all 45 drives?
OS is RHEL 7, LVM version is 2.02.115(2)-RHEL7.