DC/UCF Concepts › Storage Pools › Segregating User and System Storage

Segregating User and System Storage

As mentioned in the previous section, segregating user and system storage helps to prevent the system from stalling when a user program uses large amounts of storage. This storage segregation is also a prerequisite for enabling the High Performance Storage Protect feature.

Note: For more information about the High Performance Storage Protect feature, see Storage Protection.

System generation permits defining four types of user-oriented storage: user, user-kept, shared, and shared-kept, as well as two types of system storage: database and terminal.

The storage pools must be defined in such a manner that all forms of user-oriented storage are segregated from the system storage. In other words, define both an XA and a non-XA storage pool for user storage types. Storage types: user, user-kept, shared, and shared-kept, can be together, but they must be defined to secondary storage pools and must be isolated from any storage pools that contain database or terminal type storage.

To segregate user and system storage, perform the following steps:

1. In SYSGEN, define at least one storage pool in the range 128 to 254 to support types user, user-kept, shared, and shared-kept. In addition, no pool can be defined to support type ALL (the default) or a mixture of these types and system (database or terminal) storage.
2. To remove user storage types from pool 0, you must SYSGEN at least one pool in the range of 1 to 127 that supports types user, user-kept, shared, and shared-kept. In addition, no pool can be defined to support type ALL (the default) or a mixture of these types and system (database or terminal) storage.