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

C program, program to find minimum total number of shelfs

program to find minimum total number of shelfs

What is dots per inch, Q. What is Dots per Inch? DPI (Dots per Inch) is...

Q. What is Dots per Inch? DPI (Dots per Inch) is a measure for actual sharpness of onscreen image. This relies on both the resolution and size of the image. Practical experienc

Basic operational concepts of a computer, Basic Operational Concepts of a C...

Basic Operational Concepts of a Computer: Most of computer operations are executed in the ALU (arithmetic and logic unit) of a processor. For an example: to add 2 numb

What are disadvantages of eprom, What are disadvantages of EPROM? The c...

What are disadvantages of EPROM? The chip must be physically removed from the circuit for reprogramming and its whole contents are erased by the UV light.

Collision free network, Hello Sir/Mam, Actually i am trying to implement th...

Hello Sir/Mam, Actually i am trying to implement the concept of MAC layer protocols in NS2..... But unfortunately i am not able to do that.... and not even able to get the code fo

What is sap luw or update transaction, What is SAP LUW or Update Transactio...

What is SAP LUW or Update Transaction? Update transaction (or "SAP LUW") This is a set of updates terminated by an ABAP/4 commit.  A SAP LUW may last much longer than a data

Main drawbacks of cd-roms, Q. Main drawbacks of CD-ROMs? The main drawb...

Q. Main drawbacks of CD-ROMs? The main drawbacks of CD-ROMs are: It is read only thus can't be updated Access time is longer than that of magnetic disks. Very

What are the techniques of data collection, What are the techniques of Data...

What are the techniques of Data Collection It can be either automatic or manual. Manual techniques can include: -  Keypads/Keyboards to type in data -  touch screens to s

Mapping design principle, The following definition of mapping is adapted fr...

The following definition of mapping is adapted from the first edition of the Set Book: Mapping concerns the relationship between controls and their effects in the world. Nearly al

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