Asus Adaptec 2025 ZCR - Manual (Page 146)

E-3
About RAID
RAID 1 offers no write performance advantage over a simple
volume configuration. However, because the drives share read load
equally, RAID 1 provides improved read performance. An example
of a RAID 1 array is shown below.
RAID 5
This RAID type requires at least three drives. Like RAID 0, data is
striped across the drives. However, in RAID 5, parity is stored
separately from data, and occupies the equivalent of one drive. The
controller generates parity every time data is written to the array,
and it is distributed in stripes across all the drives.
In the event of a drive failure, the contents of the failed drive can be
rebuilt from the data and parity on the remaining drives.
RAID 1
Data 0
Drive Drive
Data 1
Data 2
Data 3
Data 0
Data 1
Data 2
Data 3
RAID 5
Data 3
Data 0
Parity 3
Data 6
Data 4
Data 1
Data 9
Parity 2
Parity 1
Data 2
Data 10
Data 7
Parity 0
Data 5
Data 11
Data 8
Drive Drive Drive Drive