Memory resident page table dram vp 2 vp 3 vp 4 vp

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Unformatted text preview: able (DRAM) VP 2 VP 3 VP 4 VP 6 VP 7 Virtual Memory as Cache PP 0 PP 3 University of Washington Page Fault ¢  Page fault: reference to VM byte that is NOT in physical memory Virtual address Physical page number or Valid disk address PTE 0 0 null 1 1 0 1 0 0 PTE 7 1 null Physical memory (DRAM) VP 1 VP 2 VP 7 VP 4 Virtual memory (disk) VP 1 Memory resident page table (DRAM) What happens when a page fault occurs? VP 2 VP 3 VP 4 VP 6 VP 7 Virtual Memory as Cache PP 0 PP 3 University of Washington Fault Example: Page Fault ¢  ¢  User writes to memory locaKon That porKon (page) of user’s memory is currently on disk 80483b7: c7 05 10 9d 04 08 0d User Process movl ¢  ¢  movl $0xd,0x8049d10 OS excep)on: page fault returns ¢  int a[1000]; main () { a[500] = 13; } Create page and load into memory Page handler must load page into physical memory Returns to faulKng instrucKon: mov is executed again! Successful on second try Virtual Memory as Cache University of Washington Handling Page Fault ...
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This document was uploaded on 04/04/2014.

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