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

Correct the code for visitor and vehicle portion, Gopher Gallery consists o...

Gopher Gallery consists of a shopping mall and a cart ride that covers the 150 acre habitat. There are m visitors and n single-person vehicles. Visitors stroll around the mall at t

Cpu, Some CPUs provide for more than two modes of operation. What are two p...

Some CPUs provide for more than two modes of operation. What are two possible uses of these multiple modes?

Explain the communications of request or response interface, Explain the Co...

Explain the Communications of Request or Response Interface The inter-application communication must provide four specific interface to the CSInterface() components. A client m

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 the scheduling in multitasking, Define the Scheduling in Multitaskin...

Define the Scheduling in Multitasking Earlier we learned the concepts and advantages of multitasking. In a system in which one or more tasks( threads or processes) attempt to s

Mechanism for code and data sharing, Q. Consider a system in which a progr...

Q. Consider a system in which a program is able to be separated into two parts: code and data. The CPU recognizes whether it wants an instruction (instruction fetch) or data (data

What is the lower bound on the numeral of page faults, Q. Presume that you...

Q. Presume that you have a page-reference string for a process with m frames (initially all empty). The page-reference string has length p along with n distinct page numbers

Hardware and software requirements for virtual memory?, What are the hardwa...

What are the hardware and software requirements for virtual memory? The hardware required for virtual memory is a secondary memory and page table. The page table should have th

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