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

What do you mean by u-area or u-block, What do you mean by u-area (user are...

What do you mean by u-area (user area) or u-block? This having the private data that is manipulated only by the Kernel. This is local to the Process, i.e. every process is a

Fuzzy logic - artificial intelligence, Fuzzy set theory provides a means fo...

Fuzzy set theory provides a means for modeling the kind of uncertainty associated with vagueness, with imprecision, and/or with a lack of information regarding a particular element

What are the functions of dispatcher, What are the functions of dispatcher?...

What are the functions of dispatcher? There are four fuctions of dispatcher:- A)  Equal distribution of transaction load to the work processes.  B) Management of buffer a

Logical user-centered interactive design methodology, Question: Logical...

Question: Logical User-Centered Interactive Design Methodology is a methodology that identifies six clear stages to help in software development while keeping the user in mind.

Explain erasable programmable rom (eprom) - computer memory, Explain Erasab...

Explain Erasable Programmable ROM (EPROM) - Computer Memory? An EPROM is a ROM that can be reprogrammed and erased. A little glass window is installed at the top of the ROM pac

Digital forensic investigation, (a) Name five important activities invol...

(a) Name five important activities involved in a digital forensic investigation. (b) Briefly describe the three types of data that a forensic examiner has to work with. Whic

What is ai, Artificial intelligence ("AI") can mean a lot of things too man...

Artificial intelligence ("AI") can mean a lot of things too many people. Much confusion arises that the word 'intelligence' is ill-defined. The phrase is so broad that people have

How do the registers help in instruction execution, Q. How do the registers...

Q. How do the registers help in instruction execution? We will discuss this in following steps: Step 1: First step of instruction execution is to fetch instruction which

Determine a positive logic system logic state level, In a positive logic sy...

In a positive logic system, logic state 1 corresponds to ? Ans. For positive digital logic, we choose two voltages levels. Higher voltage shows logic 1 and a lower voltage sho

Pre-os and runtime sub-os functionality, In a raw Itanium, a 'Processor Abs...

In a raw Itanium, a 'Processor Abstraction Layer' (PAL) is incorporated in system. When it's booted PAL is loaded in the CPU and provides a low-level interface which abstracts a nu

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