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

Cycle time, when demand is 24000 units/year, production rate is 48000 units...

when demand is 24000 units/year, production rate is 48000 units/year, setup cost is rs 200 per setup, carring cost is rs 20 per units/year, and economic batch quantity is 692.8203

Array-initialization loops using lru replacement algorithm, Q. Consider th...

Q. Consider the two-dimensional array A: int A[][] = new int[100][100]; Whereas A [0][0] is at location 200 in a paged memory system with pages of size 200. A little process

Explain the thread local storage (tls), Explain the Thread Local Storage (T...

Explain the Thread Local Storage (TLS)    Windows NT provides unique functions for per-thread data management. Thread local storage (TLS) is a concept defined in NT so develope

Characteristics of suspend process, Characteristics of suspend process ...

Characteristics of suspend process Suspended process isn't immediately available for execution. The process may or may not be waiting on an event. For preventing t

PSEUDO CODE FOR PROGRAM, THE PROGRAM WILL CHOOSE TWO RANDOM NUMBERS,THEN PR...

THE PROGRAM WILL CHOOSE TWO RANDOM NUMBERS,THEN PRINT THEM OUT AS AN ADDITION PROBLEM.THE PROGRAM WILL THEN ASK THE USERTO ENTER THE CORRECT ANSWER.IF THE ANSWER IS CORRECT,THE PRO

Architects applications by making use of multitasking, Architects Applicati...

Architects Applications by Making Use of Multitasking As the capability of computer hardware keeps increasing, operating systems are presented with overwhelming opportunities.

What are the advantages and disadvantages of multithreading, What are the a...

What are the advantages and disadvantages of multithreading?  Advantages : Since by multithreading multiple executions are carried out in the same process environment t

Unix script, As a group, you may need to make some enhancements to your dev...

As a group, you may need to make some enhancements to your development server (NOT your stable server!)  It needs to be able to run the makepasswd program, which may require instal

What are the benefits of multithreaded programming, What are the benefits o...

What are the benefits of multithreaded programming? The advantages of multithreaded programming can be broken down into four main categories: Responsiveness Resourc

Explain about paging, Explain about paging? Answer: Paging is a memory-...

Explain about paging? Answer: Paging is a memory-management scheme that permits the physical-address space of process to be noncontiguous. Paging avoids the considerable proble

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