HP-UX 11i Internals

Virtual Memory Support

In a virtual memory system, pages are mapped from one set of addresses, virtual addresses, to another set, physical addresses. Each time the processor accesses memory, it does so using a virtual address. This address then gets translated to a physical address. This mapping takes place in units of pages. When a program addresses a virtual address, that address is first broken up into a virtual page number and an offset into that virtual page. The virtual page is then translated into a physical page. It's possible that the virtual page might be on disk rather than in physical memory. In this case, a page fault is generated and the page must then be brought in from disk to memory. In this section we look at how addresses get ...