Memory allocation in a demand-paging virtual storage operating system such as OS/2 embodies the allocation of a number of system resources with certain attributes applied:
Resources
Virtual address space
Real address space
Auxiliary address space (SWAPPER)
Attributes
Exclusion (privacy)
Inclusion (sharing)
Owner (Where is was allocated from or who it was allocated to)
Requestor (who made the request on behalf of the owner)
Permissions (Read-only, Read/Write, Executable)
Use of the resources and the attributes applied is tracked by the system in its VM control blocks. The most important of these are:
VMAH