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n |
A memory
reference to an unused page traps into
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the OS
(protection violation)
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n |
Each PTE also
contains:
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u |
a present bit
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F |
If set: 20 bits
are used for the frame address of
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the selected
page.
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F |
Else these bits
are used to locate the selected
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page in a paging
file (on disk)
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u |
some bits
identify the paging file used
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u |
a dirty bit (ie: a modified bit)
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u |
some protection
bits (ex: read-only, or read-write)
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