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| The NRU Replacement |
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| Algorithm |
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| ä | Replaces
one of the pages that has not been |
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| recently
used |
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| ä | Two
status bits are associated with each page in |
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| memory. |
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| ä | The
R bit is set when the page is referenced |
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| ä | The
M bit is set when the page is modified |
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| ä | The
pages can be divided into 4 categories: |
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| ä | not
referenced, not modified |
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| ä | not
referenced, modified |
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| ä | referenced,
not modified |
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| ä | referenced,
modified |
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