Demand Paging on Symbian OS

As ARM-based mobile phones become increasingly feature-rich, so the demand on system resources increases. One important commodity is physical RAM, which contributes significantly to the Bill Of Materials (BOM) of a device. Demand Paging (DP) involves making the contents of memory available to a program at the time they are required - that is, 'on demand.' When the contents are no longer required, the RAM used to store them may be reused for other content. In this way, the total RAM required to store content is less than if it were all permanently available. Since less physical RAM is required, the overall BOM may be reduced.