Raid 5 - Block Striping With Distributed Parity - AMD M3A78-EMH HDMI User Manual

RAIDXpert User Manual
RAID 5 – Block Striping with Distributed Parity
RAID 5 stripes data and distributes parity information across the physical drives
along with the data blocks. This organization increases performance by
accessing multiple physical drives simultaneously for each operation, as well as
fault tolerance by providing parity data. In the event of a physical drive failure,
data can be re-calculated by the RAID system based on the remaining data and
the parity information.
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.
Figure 3. RAID 5 Stripes all drives with data and parity information
Data
Blocks
The capacity of a RAID 5 logical drive is the smallest physical drive size
multiplied by the number of physical drives, less one. Hence, a RAID 5 logical
drive with four 100 GB physical drives will have a capacity of 300 GB. A logical
drive with two 120 GB physical drives and one 100 GB physical drive will have a
capacity of 200 GB.
Only the AMD SB650 and SB750 Controllers support RAID 5.
RAID 5 logical drives on the AMD SB650/SB750 Controller consist of 3 or 4
physical drives.
Distributed Parity
physical drives
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