PREFERRED AREA HAS EXPANDED, RECONFIGURABILITY AND PERFORMANCE
MAY BE IMPAIRED. text.
Explanation
The real storage manager (RSM)
converted one or more non-preferred frames or 1 MB frames to preferred
frames. The system may no longer be able to reconfigure all or
part of the storage in the non-preferred area. If this expansion involves
frames below 16 megabytes, the system can page fix these frames, which
might lead to performance problems.
In the message text,
text is
one of the following:
- CHECK RSU VALUE
- When running in z/Architecture® mode
with a specified RSU of 0, there are still areas of real storage being
managed as preferred and non-preferred storage. Specifically, there
is a class of real storage frames managed in a special way called
quad frames. These frames are used primarily to hold segment tables
and must be 4 contiguous frames of real storage. The area occupied
by quad frames is treated as non-preferred storage. During times of
heavy demand for real storage, frames from the area used by quad frames
may be required for system overhead and will be reallocated for system
use for the duration of the IPL. In this case, message IAR005E is
issued.
- POSSIBLY DUE TO RECOVERY IN PROGRESS
- During recovery processing for the RSM, some available frames
might appear to be not available to the system. This condition is
temporary and will be cleared when the recovery processing completes.
System action
The system can use the newly designated frames
as preferred storage for additional long term resident pages.
Operator response
Enter a DISPLAY M command to determine the
number of frames remaining in the non-preferred area.
System programmer response
Check that the reconfigurable storage
unit (RSU) value specified in the IEASYSxx parmlib member is appropriate
for your installation. See z/OS MVS Initialization and Tuning Reference
for more information about the IEASYSxx parmlib member.
If the message indicates that recovery processing is
in progress and the RSU value is appropriate, then no further action
is required. Additional frames will become available as the recovery
processing completes.
Source
Real storage manager (RSM)
Module
Routing code
Descriptor code