PPT Slide
Page Tables
- If the number of pages gets to be too large to store in registers then we can map the page table into memory (Figure 11.9).
- Note the addition of a Page Table Base Register in place of the base register. Now a context switch involves saving/restoring one register for all the page mappings rather than a set of registers.
- Can also add a Page Table Length Register so we know on a per-process basis how large the page table is.
- Big problem though is now every memory address requires two memory accesses! Program will run at 1/2 the speed!