Raid 5 Arrays Optimize Performance, Fault Tolerance, High Capacity And Storage Efficiency; Figure 3. Raid 10 Configuration Example - 3Ware 7000-2 - Escalade RAID Controller User Manual

Introduction
arrays. RAID 10 is available on the four, eight, and twelve port
Escalade ATA RAID Controllers.

Figure 3. RAID 10 Configuration Example

Raid 5 arrays optimize performance, fault
tolerance, high capacity and storage
efficiency
The RAID 5 configuration features the data striping of RAID 0
combined with the parity of RAID 4. Using a simple parity (exclu-
sive OR) function, RAID 5 can tolerate the loss of one drive. Parity
information is distributed across all drives rather than being con-
centrated on a single disk (see Figure 4). This avoids throughput
loss due to contention for the parity drive. You can use hot spares to
rebuild a failed drive "on-the-fly".
×
RAID 5 capacity = size of smallest drive (number of drives - 1).
In addition, the array's storage efficiency increases with the number
of disks; from 66.7 % for 3 drives to 87.5 % for 8 drives: storage
÷
efficiency = (number of drives -1) (number of drives).
Unlike all other RAID configurations that offer data striping, except
for RAID 1, RAID 5 stripe size is limited to 64k.
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