NovaScale r410 e1, User Manual, Page: 121 / 325

User Guide
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RAID 5
RAID level 5 organizes data across the disk drives of the logical drive, and
distributes parity information across the disk drives along with the data blocks.
This organization allows increased performance by accessing multiple disk drives
simultaneously for each operation, as well as fault tolerance by providing parity
data. In the event of a disk drive failure, data can be re-calculated by the RAID
system based on the remaining data and the parity information.
The adjustable block size of the RAID 5 logical drive allows for performance
tuning based on the typical I/O request sizes for your system. The block size must
be set at the time the logical drive is created and cannot be adjusted dynamically.
RAID 5 makes efficient use of hard drives and is the most versatile RAID Level. It
works well for file, database, application and web servers.
The capacity of a RAID 5 logical drive is the smallest disk drive size multiplied by
the number of disk drives, less one. Hence, a RAID 5 logical drive with four 100
GB disk drives will have a capacity of 300 GB. A logical drive with two 120 GB
disk drives and one 100 GB disk drive will have a capacity of 200 GB.