Explain Not recently used page replacement algorithm, Computer Engineering

Assignment Help:

Not Recently Used Page Replacement Algorithm

The not recently used abbreviated as NRU page replacement algorithm works on the subsequent principle: while a page is referenced, a referenced bit is set for that page, marking it as referenced. Likewise, while a page is modified (written to), a modified bit is set.  At a specific fixed time interval, the clock interrupt triggers and clears the referenced bit of all the pages, thus only pages referenced in the current clock interval are marked with a referenced bit. When a page requires to be replaced, the operating system categorizes the pages into four classes:

a) Class 0: not referenced, not modified 
b) Class 1: not referenced, modified 
c) Class 2: referenced, not modified 
d) Class 3: referenced, modified.

The NRU (Not recently used) algorithm picks a random page from the lowest category for removal. 


Related Discussions:- Explain Not recently used page replacement algorithm

Corresponding port numbers, A) Around how many entries are there in this fi...

A) Around how many entries are there in this file on your VM? B) Select and list names and corresponding port numbers for four well-liked services listed in this file?

How does the race condition occur, It happens when two or more processes ar...

It happens when two or more processes are reading or writing some joint data and the final result depends on who runs exactly when.

Design a mod-12 synchronous up counter, Design a mod-12 Synchronous up coun...

Design a mod-12 Synchronous up counter. Ans. Design of a mod 12 synchronous counter by using D-flipflops. I state table Present state                                   Next

Explain about behavioral notations, Explain about Behavioral Notations ...

Explain about Behavioral Notations These notations contain dynamic elements of the model.  Their elements comprise interaction and the state machine. It also comprise classe

What is pci bus, What is PCI bus? The Peripheral component interconnect...

What is PCI bus? The Peripheral component interconnect(PCI) bus is a standard that handles the functions found on a processor bus but in a standardized format that is independe

What is meant by stacked list, What is meant by stacked list? A stacke...

What is meant by stacked list? A stacked list is nothing but secondary list and is showed on a full-size screen unless you have specified its coordinates using the window comm

Processors hypercube and utilisation displays, Processors Hypercube Thi...

Processors Hypercube This is specific to in the hypercube: Here, every processor is depicted by the set of nodes of the graph and the several arcs are represented with communic

What are the mechanisms for implementing i/o operation, What are the variou...

What are the various mechanisms for implementing I/O operations? a) Program controlled I/O b) Interrupts c) DMA

What are types of firewalls, What are types of firewalls? There are con...

What are types of firewalls? There are conceptually two types of firewalls as: 1. Network Level 2. Application Level

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