Disk Arm Graphs; Peak Disk Arm Utilization In % - Per Day - IBM PERFORMANCE MANAGEMENT FOR POWER SYSTEMS - GRAPH REFERENCE DOCUMENT Reference

Disk Arm Graphs

Peak Disk Arm Utilization in % - Per Day

Daily Peak Disk Arm Utilization in %, per Day.
This graph displays the average of the two peak hours for disk arm utilization, for each day
during the last three months, or the period you choose.
The arm utilization is a reflection of the disk arms assigned to the partition, whether internal or
external arms. It does not differentiate between disk manufacturers or disk types.
The information under the Facts heading at the bottom of the graph states the recommended
guidelines for marginal and critical peak utilization and the months calculated to reach this
guideline, based on your current arm usage and growth trends.
Note for systems with SAN-based storage:
Each server/LPAR's graph for disk arms will reflect utilization of the portion of the SAN that is
accessed by that server/LPAR. In rare cases, multiple servers using storage on the same SAN
unit may result in a slight increase in displayed disk arm utilization.
PM for Power Systems Graph Reference Document 29