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| n |
Pages to be
replaced are kept in main memory for a
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while to guard
against poorly performing
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replacement
algorithms such as FIFO
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| n |
Two lists of
pointers are maintained: each entry
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points to a
frame selected for replacement
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u |
a free page list for frames that have not been
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modified since
brought in (no need to swap out)
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u |
a modified page list for frames that have been
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modified (need to
write them out)
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| n |
A frame to be
replaced has a pointer added to the
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tail of one
of the lists and the present bit is cleared
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in
corresponding page table entry
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u |
but the page
remains in the same memory frame
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