 |
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| n |
At each page
fault the two lists are first examined
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to see if the
needed page is still in main memory
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u |
If it is, we just
need to set the present bit in the
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corresponding
page table entry (and remove the
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matching entry in
the relevant page list)
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u |
If it is not,
then the needed page is brought in, it is
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placed in the
frame pointed by the head of the free
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|
frame list
(overwriting the page that was there)
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F |
the head of the
free frame list is moved to the next entry
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u |
(the frame
number in the page table entry could be used
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|
to scan the two
lists, or each list entry could contain the
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process id and
page number of the occupied frame)
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| n |
The modified
list also serves to write out modified
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pages in
cluster (rather than individually)
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|
