Memory pool allocation

When you start a subsystem, the system attempts to allocate the user-defined storage pools that are defined in the subsystem description of the started subsystem.

If the system cannot allocate all of the requested storage, it will allocate as much storage as is available and then allocate the remainder of the storage as it becomes available. For example, consider the following table. If 700KB is available, and if *SHRPOOL2 is defined to 500KB, then 300KB is allocated to the first storage pool and 400KB is allocated to the second storage pool.

Pool ID Specified in SBSD	1	2
Storage Requested	300K	*SHRPOOL2
System Pool ID	3	4
Storage Allocated	300K	400K
Activity Level	1
Pool Type	Private	Shared

The storage pools that you define decrease the size of the Base memory pool when they are allocated. The system only allocates as much storage to a private pool as it has available in the Base memory pool. The Base memory pool minimum size (QBASPOOL) system value determines the minimum Base pool size.