A lot of attention is required when the disk subsystem is designed and implemented. For example, you will need to consider the following:
Bandwidth of disk adapters and system bus
Placement of logical volumes on the disks
Configuration of disk layouts
Operating system settings, such as striping or mirroring
Performance implementation of other technologies, such as SSA
Do not make any changes to the default disk I/O parameters until you have had experience with the actual workload. Note, however, that you should always monitor the I/O workload and will need to balance the physical and logical volume layout after runtime experience.
There are two performance-limiting aspects of the disk I/O subsystem ...