Single-level page tables, Operating System

Assignment Help:

As mentioned above, page tables, are lookup tables mapping a process' virtual pages to physical pages in RAM. How would one implement these page tables?

The most straightforward approach would simply have a single linear array of page-table entries (PTEs). Each PTE contains information about the page, such as its physical page number ("frame" number) as well as status bits, such as whether or not the page is valid, and other bits to be discussed later.

If we have a 32-bit architecture with 4k pages, then we have 2 pages, as discussed in the last lecture. If each PTE is 4 bytes, then each page table requires 4 Mbytes of memory. And remember that each process needs its own page table, and theremay be on the order of 100 processes running on a typical personal computer. This would require on the order of 400 Mbytes of RAM just to hold the page tables on a typical desktop!

Furthermore, many programs have a very sparse virtual address space. The vast majority of their PTEs would simply be marked  invalid.Clearly, we need a better solution than single-level page tables.


Related Discussions:- Single-level page tables

Server thread, Extend task 1 so that the requests are issued by the clients...

Extend task 1 so that the requests are issued by the clients instead of the server. The server now do not use the "all_requests.dat" file. Instead every client thread reads from

Prolog application, 1. Problem Domain You will be considering the Wumpus ...

1. Problem Domain You will be considering the Wumpus world introduced in Russell and Norvig (2009) Chapter 7. For this programming assignment you'll use Prolog's ability to do in

Logic gates, Determine the equation for the y and truth table for the circu...

Determine the equation for the y and truth table for the circuits

Define approaches that require knowledge of the system state, Define approa...

Define approaches that require knowledge of the system state?  Answer: Deadlock detection, Deadlock prevention, Deadlock Avoidance.

Describe the main architectural layers of windows xp, Q. Describe the three...

Q. Describe the three main architectural layers of Windows XP? Answer: (1) The HAL (Hardware Abstraction Layer) creates operating system portability by hiding hardware differ

Write a note on the usage of semaphores, Write a note on the usage of semap...

Write a note on the usage of semaphores. Semaphore is a synchronization tool and it is a variable having integer values. It is accessed only by two standard atomic operations w

Why do systems store the operating system in firm ware, Q. Why do several s...

Q. Why do several systems store the operating system in firm ware and others on disk? Answer: For certain devices such like handheld PDAs and cellular telephones a disk with

What is the sequence of a page fault causes to occur, A page fault causes t...

A page fault causes the following sequence to occur. 1. Trap (shut in) to the operating system. 2. Save the process registers and process state. 3. Verify that the interr

Determine what the expansion of nested macro calls follows, Determine what ...

Determine what the expansion of nested macro calls follows  The expansion of nested macro calls follows the Last in First out (LIFO) rule.

Define criterion for classification of data structures, Define what can be ...

Define what can be used as a criterion for classification of data structures utilized in language processing              Answer: nature of a data structure, lifetime of a dat

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd