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CHAPTER
9 Hardware/Software Trade-Offs
memory management unit. If a local page mapping is found, the cache hierarchy is
looked up and it behaves just like a regular uniprocessor operation. If a local page
mapping is not found, a page fault occurs and then the page is mapped in, providing
a physical address. If the operating system indicates that the page is not currently
mapped on any other node, then it is mapped in from disk with read-write permis-
sion, otherwise it is obtained from another node with read-only permission. Now
the cache is looked up. If inclusion is preserved between the local memory and the
cache hierarchy, as it normall ...