Our system is using virtual memory and has 48-bit virtual address space and 32-bit physical address space. Page size is 16 KiB. (a) How many entries are needed for a single-level page table? What does the two-level page table look like if the part of the virtual address which identifies the page number is split into two fields of equal size? (b) Our system also has the TLB (Translation Lookaside Buffer) with 128 entries. We run the following program which reads 32-bit integers from an array of size 200 000: int[] t = new int [200000]; for (int i=399; i>=0; i--) { for (int j = 0; j<500; j++) { } } // we access t[i+ 400 * j ] How efficient is the TLB in this case? More precisely, how many times will a TLB miss occur (resulting in page table lookup)? Assume that the TLB is initially empty.

Our system is using virtual memory and has 48-bit virtual address space and 32-bit physical address space. Page size is 16 KiB. (a) How many entries are needed for a single-level page table? What does the two-level page table look like if the part of the virtual address which identifies the page number is split into two fields of equal size? (b) Our system also has the TLB (Translation Lookaside Buffer) with 128 entries. We run the following program which reads 32-bit integers from an array of size 200 000: int[] t = new int [200000]; for (int i=399; i>=0; i--) { for (int j = 0; j<500; j++) { } } // we access t[i+ 400 * j ] How efficient is the TLB in this case? More precisely, how many times will a TLB miss occur (resulting in page table lookup)? Assume that the TLB is initially empty.

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter11: Operating Systems

Section: Chapter Questions

Problem 26VE

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Similar questions

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