In this exercise, we will examine space/time optimizations for page tables. The following list provides parameters of a virtual memory system. Physical DRAM Installed Page Size 4 KiB PTE Size (byte) 4 16 GiB (a) For a single-level page table, how many page table entries (PTES) are needed? How much physical memory is needed for storing the page table? Virtual Address (bits) 43 (b) Using a multilevel page table can reduce the physical memory consumption of page tables, by only keeping active PTEs in physical memory. How many levels of page tables will be needed if the segment tables (the upper-level page tables) are allowed to be of unlimited size? And how many memory references are needed for address translation if missing in TLB? (c) An inverted page table can be used to further optimize space and time. How many PTES are needed to store the page table? Assuming a hash table implementation, what are the common case and worst case numbers of memory references needed for servicing a TLB miss?

In this exercise, we will examine space/time optimizations for page tables. The following list provides parameters of a virtual memory system. Physical DRAM Installed Page Size 4 KiB PTE Size (byte) 4 16 GiB (a) For a single-level page table, how many page table entries (PTES) are needed? How much physical memory is needed for storing the page table? Virtual Address (bits) 43 (b) Using a multilevel page table can reduce the physical memory consumption of page tables, by only keeping active PTEs in physical memory. How many levels of page tables will be needed if the segment tables (the upper-level page tables) are allowed to be of unlimited size? And how many memory references are needed for address translation if missing in TLB? (c) An inverted page table can be used to further optimize space and time. How many PTES are needed to store the page table? Assuming a hash table implementation, what are the common case and worst case numbers of memory references needed for servicing a TLB miss?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Suppose you have a byte-addressable virtual address memory system with 16 virtual pages of 64 bytes each and 4-page frames. Assuming the following page table, answer the questions below: Page # Frame # Valid bit 0 2 1 1 3 1 2 - 0 3 0 0 4 1 1 5 - 0 6 - 0 7 - 0 A. What physical address corresponds to the virtual address 0x42? Answer should be in hexadecimal number. (if the address causes a page fault, answer as "page fault" with the proper explanation) B. What physical address corresponds to the virtual address 0x72? Answer should be in hexadecimal number. (if the address causes a page fault, answer as "page fault" with the proper explanation) C. What physical address corresponds to the virtual address 0x84? Answer should be in hexadecimal number. (if the address causes a page fault, answer as "page fault" with the proper explanation)
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