SQA is allocated in fixed storage upon demand as long-term fixed storage and remains so until explicitly freed. The number of central frames assigned to SQA may increase and decrease to meet the demands of the system.

All SQA requirements are allocated in 4K frames as needed. These frames are placed within the preferred area (above 16 megabytes, if possible) to keep long-term resident pages grouped together.

If no space is available within the preferred area, and none can be obtained by stealing a non-fixed/unchanged page, then the "reconfigurable area" is reduced by one storage increment and the increment is marked as preferred area storage. An increment is the basic unit of physical storage. If there is no "reconfigurable area" to be reduced, a page is assigned from the V=R area. Excluded from page stealing are frames that have been fixed (for example, through the PGFIX macro), allocated to a V=R region, placed offline using a CONFIG command, have been changed, have I/O in progress, or contain a storage error.