CITS2002 Systems Programming  
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Paging vs Partitioning

When we compare paging with the much simpler technique of partitioning, we see two clear benefits:

  • As processes are swapped-out and then back in, they may occupy different regions of physical memory.

    This is possible because hardware efficiently translates each logical address to a physical address, at run-time.

    The operating system's memory management software manipulates the hardware (page table registers) to facilitate the translation.

  • A process is broken into pages and these need not be contiguous in physical memory.

In combination with the principle of referential locality, we now have a significant breakthrough:

If the above two characteristics are present, then it is not necessary for all pages of a process to be in memory at any one time during its execution.

 


CITS2002 Systems Programming, Lecture 14, p2, 12th September 2023.