12 DS8800 Performance Monitoring and Tuning
Use the automatic mode of Easy Tier to relocate your extents to their most appropriate
storage tier in a hybrid pool, based on usage. Because workloads typically concentrate I/O
operations (data access) on only a subset of the extents within a volume or LUN, automatic
mode identifies the subset of your frequently accessed extents. It then relocates them to the
higher-performance storage tier.
Subvolume or sub-LUN data movement is an important option to consider in volume
movement because not all data at the volume or LUN level becomes hot data. For any
workload, there is a distribution of data considered either hot or cold. Significant overhead
can be associated with moving entire volumes between ...