Address Mapping Algorithm

• If V = 1

  • then page is in main memory at frame address stored in table
  • else page is in secondary storage

• Page Fault

  • page not resident in physical memory (V = 0)
  • causes an exception
  • operating system initiates fetch from secondary storage
  • usually accompanied by a context switch: current process suspended while page is fetched from secondary storage

• Access Control

  • R = Read-only, R/W = read/write, X = execute only

• Protection Fault

  • access control violation
  • access type (load/store) not allowed by specified access rights (read/write)

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