Hierarchical storage management balancing

Hierarchical storage management (HSM) balancing can only be used auxiliary storage pools (ASPs) that contain a mixture of compressed and non-compressed disk units.

The Trace Auxiliary Storage Pool Balance (TRCASPBAL) command must finish collecting statistics before hierarchical storage management balancing can begin. When you use hierarchical storage management balancing, the high use and low use data on each unit in the ASP is redistributed. The high use data is moved to high performance units and the low use data is moved to low performance units. After the balance activity has completed, the system clears the trace information.