Memory Manager keep list of different pages depending on the state of the Pages. It helps in managing the Page frame resource for the system. As and when need arise, Memory manager moves Pages between these lists. Following is small description of different Page lists maintained in the system:
- Working Set: Pages (physical) those are assigned to a Process/System address space are maintained in this set.
- Modified Page List: Pages that were written to and are removed from the Working Set are maintained in this list till the content are synced back to the pagefile. Once it is synced back to the Pagefile, the Page is moved to the Standby list.
- Standby list: Pages in this list have almost same status as it would be in the Working Set. If need arise, it can be quickly moved back (soft page fault) to the Working Set without much work. It contain valid and most current content so no Page In I/O is required to reuse it again. Pages in this list were taken out of Working Set (sometime via Modified Page list) and were added to this list, probably for the reason that Process is not using them at the moment.
- Free Page List: Pages are available for use. Contain invalid data. So it need proper initialization.
- Zero Page List: Pages are available for use. Initialized to Zero. Used in case of Demand Zero Page request.
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