Paged virtual memory

Global vs. local frame allocation

If a process needs frames, should pages from other processes be discarded, or just pages from the process which wants frames? Local policy means giving each process a share of the physical memory, and swapping pages in and out on a per process basis. Trouble is how many frames to allocate to each process? Processes' working sets can grow and shrink rapidly: global policy accommodates this more easily.


last updated 18 March 1998