In a demand paging system, the page table is stored in RAM. Processor access (read or write a word) time to RAM is given as R, time to read a frame from hard disk is DR and time to write a frame to hard disk is DW. If page fault probability is F, and the probability that a page to be swapped out is dirty is D, what is the expression that correctly represents the average memory access time? OR+ (1- F) * R+D* DR + (1– D) * DW OR+ (1- F) * DR +F*( DR + (1 – D) * (DR + DW)) O 2*R+F* (DR + D 'DW) R-E:1- DI: D W +D:DR+ RI

In a demand paging system, the page table is stored in RAM. Processor access (read or write a word) time to RAM is given as R, time to read a frame from hard disk is DR and time to write a frame to hard disk is DW. If page fault probability is F, and the probability that a page to be swapped out is dirty is D, what is the expression that correctly represents the average memory access time? OR+ (1- F) * R+D* DR + (1– D) * DW OR+ (1- F) * DR +F( DR + (1 – D) (DR + DW)) O 2R+F (DR + D 'DW) R-E:1- DI: D W +D:DR+ RI

Operations Research : Applications and Algorithms

4th Edition

ISBN:9780534380588

Author:Wayne L. Winston

Publisher:Wayne L. Winston

Chapter20: Queuing Theory

Section20.13: Closed Queuing Networks

Problem 1P

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