What is meant by demand paging? explain, Operating System

Assignment Help:

What is meant by demand paging? Explain.

Demand paging is a technique to implement virtual memory. In demand paging simply when a page is required it is brought into memory. As an alternative of swapping the whole process into memory only the required pages are brought into the memory. Therefore it will not read pages which are not used and hence results in reduced swap time and memory needed.

For distinguishing the pages in memory and those on disk a valid invalid bit is used. If the bit is valid the page is in memory moreover the page is either not in memory or is not valid. The page table entry for a page that isn't currently in the memory is marked invalid.

 

 


Related Discussions:- What is meant by demand paging? explain

Define process swapping , Swapping : Whole process is moved from the swap...

Swapping : Whole process is moved from the swap machine to the main memory for execution. Process size must be equal or less than to the used main memory. It is easier to exe

Define where a program generation activity aims, Define where a Program gen...

Define where a Program generation activity aims  Program generation activity aims at Automatic generation of program

List the task regions in the spiral model, List the task regions in the Spi...

List the task regions in the Spiral model.  Customer communication - In this region it is suggested to set up customer communication.  Planning - All planning activities

State the advantage of multiprocessor system, State the advantage of multip...

State the advantage of multiprocessor system? The advantages of multiprocessor system are:- a)      Enhanced throughput. b)      Economy of scale. c)       Enhanced re

Explain signal handling, Signal handling A signal is used in UNIX syste...

Signal handling A signal is used in UNIX systems to inform a process that a particular event has occurred. 1. A signal is produced by the occurrence of a particular event.

Use of c and c++, One reason to learn C and C++ is simply that so much soft...

One reason to learn C and C++ is simply that so much software is written in these languages. A related, butmore fundamental reason, is that C and C++ are relatively low-level, allo

List the four steps that are essential to run a program, List the four step...

List the four steps that are essential to run a program on a completely dedicated machine. a. Reserve machine time. b. Manually load program into memory. c. Load starting

Explain doscreatethread functions used in the os/2, Explain DosCreateThread...

Explain DosCreateThread Functions Used in the OS/2  DosCreateThread(&threadID,MyThreadFunction,arg,flags,stackSize) DosCreateThread creates a thread within the context of th

Operating system as user interface, Q. Operating System as User Interface? ...

Q. Operating System as User Interface? • Every general purpose computer comprises the operating system, hardware, system programs and application programs. The hardware compris

Capability lists are typically kept within the address space, Q. Capabilit...

Q. Capability lists are typically kept within the address space of the user. How does the system make sure that the user cannot modify the contents of the list? Answer: An ap

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