Designing a striped logical volume
You must provide certain information to define a striped logical volume.
When a striped logical volume is defined, you specify:
- drives
- At least two physical drives. The drives used should have little other activity when the performance-critical sequential I/O is taking place. Some combinations of disk adapter and disk drive requires dividing the workload of a striped logical volume between two or more adapters.
- stripe unit size
- Although this can be any power of 2 from 4 KB through 128 KB, take sequential read-ahead into account, because that will be the mechanism that issues most of the reads. The objective is to have each read-ahead operation result in at least one I/O, ideally an equal number, to each disk drive (see previous figure).
- size
- The number of physical partitions allocated to the logical volume must be an integral multiple of the number of disk drives used.
- attributes
- The striped logical volumes can be mirrored and copies can be set to a value more than 1.