8.3. Paging Control
HP-UX systems use a variety of strategies for handling high demand on memory resources. These include paging, swapping, deactivation, memory management, and locking.
Paging is the process by which memory pages are brought into memory and removed from memory. Various algorithms for paging have been used in different HP-UX systems. Page-ins occur when a process starts up, when a process requests dynamic memory, and during page faults after a page-out, a swap-in, or a reactivation. Page-ins are always performed as needed. Code that is never executed never gets paged in.
Page-outs and page-frees occur when memory is scarce. The pager daemon vhand (further described below) does page-outs only for dirty data pages; ...