ABCs of z/OS System Programming Volume 3 - IBM Redbooks

5.4 Service level objectives
What performance objectives are required by data
When and how to back up data
Whether data sets should be kept available for use
during backup or copy
How to manage backup copies kept for disaster
recovery
What to do with data that is obsolete or seldom
used
Figure 5-4 Service level objectives
Service level objectives
To allow your business to grow efficiently and profitably, you want to find ways to control the
growth of your information systems and use your current storage more effectively.
In an SMS-managed storage environment, your enterprise establishes centralized policies for
how to use your hardware resources. These policies balance your available resources with
your users' requirements for data availability, performance, space, and security.
The policies defined in your installation represent decisions about your resources, such as:
► What performance objectives are required by the applications accessing the data
Based on these objectives, you can try to better exploit cache data striping. By tracking
data set I/O activities, you can make better decisions about data set caching policies and
improve overall system performance. For object data, you can track transaction activities
to monitor and improve OAM's performance.
► When and how to back up data - incremental or total
Determine the backup frequency, the number of backup versions, and the retention period
by consulting user group representatives. Be sure to consider whether certain data
backups need to be synchronized. For example, if the output data from application A is
used as input for application B, you must coordinate the backups of both applications to
prevent logical errors in the data when they are recovered.
Chapter 5. System-managed storage 245