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accessing all physical drives when processing large I/O requests. Multiple physical
drives working in parallel increases the throughput, meaning better performance.
For smaller I/O requests (512 bytes to 4 kilobytes), it is better to have each individual
disks handle their own I/O request, improving the IOPS (I/O per second), rather than
having one tiny I/O request being handled by multiple disks.
A block size of 64k is recommended because it strikes a balance between the two I/O
usage scenarios.
Capacity (Default: Maximum)
The total amount of space you want the RAID array to take up. When creating RAID
levels, disk capacities are limited by the smallest disk.
An example of how disk capacities are limited by smallest disk.
You have 3 drives connected to the enclosure.
The first drive is 6 TB, the second is 4 TB, and the third drive is 2 TB.
After creating a RAID level 5 using all three drives and maximum capacity, the first
drive will have 4 TB, the second 2 TB, and the third drive 0 TB of free capacity
The free capacity on the first and second drive can be used to create a separate
array.
You may also choose how much space each array will utilize. You can use the remaining
space to create another array (up to 4 arrays are supported).
Adding Spare Disks
Spare disks are physical disks that will immediately replace critical disks in an array.
To add spare disks:
1.
Click
Advanced Config.
2.
Click
Spare Pool:
