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

What is a thread, What is a thread? A thread or else called a lightweig...

What is a thread? A thread or else called a lightweight process (LWP) is a basic unit of CPU utilization, it comprises of a thread id, a program counter, a register set and a s

Differences among user-level threads and kernel-level thread, What are two ...

What are two differences among user-level threads and kernel-level threads? Under what circumstances is one type better than the other? (1) User-level threads are unknown by th

Android, Which android version is available till now

Which android version is available till now

Designing issues in a network -transparency, Transparency Users mus...

Transparency Users must be able to access remote resources as though these resources were local. Transparency should as well promote user mobility. Users must be allowed

Write a short note about context switch, Write a short note about context s...

Write a short note about context switch. Switching the CPU to another process needs saving the state of the old process and loading the saved state for the new process. This ta

Load sharing , Load Sharing : Processes are not given to a particular proc...

Load Sharing : Processes are not given to a particular processor. A global queue of threads is used to maintain. Each processor, when idle, picks a thread from this queue. Note th

List post-installation procedures that need to be performed, Problem: (...

Problem: (a) Based on your experience in setting up Windows 2003 Server operating system, briefly describe the twelve different steps in which the installation is conducted du

Thread safety, What does it mean for something to be thread-safe? By saying...

What does it mean for something to be thread-safe? By saying that X is thread-safe, we mean that if multiple threads use X at the same time, we don't have to worry about concurrenc

Process creation, what is process creation and how to create a process

what is process creation and how to create a process

Dynamic scheduling, Dynamic scheduling : The number of thread in a program...

Dynamic scheduling : The number of thread in a program may be changed during the course of operation. Dynamic priority scheduling is a kind of scheduling algorithm in which the pr

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