NEC Storage Manager User Manual page 324

Appendix E Logical Disk Used Capacity
When Y > 0,
A mode N is a congruence representing the remainder of A divided by N.
(2) Examples
When you bind 1.0-GB logical disks with RAID10 (16 PDs):
Y = (1024 + 2) mod 8 = 2
Pool used capacity = 1024 + 2 + 8 - 2 = 1032 MB
When you bind 1.0-GB logical disks with RAID10 (8 PDs):
Y = (1024 + 2) mod 4 = 2
Pool used capacity = 1024 + 2 + 4 - 2 = 1028 MB
When you bind 1.0-GB logical disks with RAID5 (10 PDs):
Y = (1024 + 2) mod 2 = 0
Pool used capacity = 1024 + 2 = 1026 MB
Note that the logical disk capacity is the same in the respective cases but the pool used capacity is
not.
Pool used capacity = X + 2 + N - Y
34