Although each Page frame can be reached directly using the Frame number and the Page size, there is also certain properties attached to each frames which are maintained separately in a database. It has one record for each Page Frame. The data structure of this record may wary per page depending on the state of that Page. But some data members are common for all. Following is description of some of the more relevant data members of PFN data structure:
- Backward/Forward Pointer: Point to the next PFN record. It is used to link the pages when they are added to different Page list (e.g. Standby, Free, Zero, Modified Page lists, etc).
- Page Priority
- Reference/Shared Count
- PTE Address/PFN of PTE: Information used to back point to PTE that was referring this page form the User/System address space.
- Original PTE Content: Use for restoring the PTE value when the Page is removed from the Working Set of Process/System.
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