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

Logic-based expert systems, Logic-based Expert Systems : Expert system...

Logic-based Expert Systems : Expert systems are agents that are programmed to make decisions just about real world situations are place together by utilising knowledge illicit

Rationales for an effective and independent regulator, Question: (a) W...

Question: (a) What are the rationales for an effective and independent regulator? (b) Across Africa, regulators have established Universal Service Funds (USFs) in order to

Write about TSR, Write about TSR TPA also holds TSR (terminate and stay...

Write about TSR TPA also holds TSR (terminate and stay resident) programs which remain in memory in an active state until activated by a hot-key sequence or another event like

What is the ''blocking factor'' of a file, The "blocking factor" of a file ...

The "blocking factor" of a file is? Ans. The number of logical records in single physical record is called the "blocking factor" of a file.

What are the necessary elements of an e-banking site, What are the necessar...

What are the necessary elements of an e-banking site? E-banking systems rely upon a number of common elements or processes. The given list comprises many of the potential elem

Standards used for development of a system, Q. Standards used for developme...

Q. Standards used for development of a system? Documentation standards: It must be an ongoing activity at the time of system development life cycle.  Quality Standards:

Explain the product of sum form - standard forms, Explain the Product of Su...

Explain the Product of Sum Form - standard forms? The POS is the Boolean Expression containing OR terms, called as sum terms. The product denotes ANDing of these terms. F= (

Define the most common biometrics, What is most common biometrics? Explain ...

What is most common biometrics? Explain in brief. The most common biometrics is as given below: Face geometry (Photo): The computer captures the picture of your face and m

Can the size of an array be declared at runtime, Can the size of an array b...

Can the size of an array be declared at runtime?              No, the size of an array can't be declared at run time, we always require to mention the dimensions of an array at

Explain direct addressing mode with example, Q. Explain Direct Addressing M...

Q. Explain Direct Addressing Mode with example? Direct Addressing Mode A direct operand signifies to contents of memory at an address referred by the name of the variable.

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