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

Addressing mode, the 68000 has rich of addressing mode . it concerned with ...

the 68000 has rich of addressing mode . it concerned with the way data is accessed . identify the destion addressing mode for EXG D0, A2

Setjmp and longjmp, How does throwing and catching exceptions differ from u...

How does throwing and catching exceptions differ from using setjmp and longjmp? Ans) The throw operation calls the destructors for automatic objects instantiated as entry to th

Reduced instruction set computer - risc, Reduced Instruction Set Computer (...

Reduced Instruction Set Computer (RISC): As we discussed before most of the modern CPUs are of the GPR (General Purpose Register) type. A few instances of such type of CPUs ar

How much frequency is centered in typical human voice, Typical human voice ...

Typical human voice is centered around                   Hz. (A)  200-400                                     (B)  280-3000  (C)  400-600

What is process, What is Process? Process: A process is a program in ...

What is Process? Process: A process is a program in execution. It is an active entity, represented through the value of the program counter and the contents of registers o

Write a short note on pointer operators in c, Write a short note on pointer...

Write a short note on pointer operators in c Pointers (that is, pointer values) are generated with the ''address-of'' operator &, which we can also think of as the ''pointer-to

What features are needed to implement top down parsing, The features are ne...

The features are needed to implement top down parsing are? Ans. Source string marker, Prediction making mechanism and also matching and backtracking mechanism features are need

Robotics, Based on the disciplines of engineering, AI and physiology robo...

Based on the disciplines of engineering, AI and physiology robotics is concerned with building robot machines with physical capabilities akin to human beings which are cont

Hiring problem algorithm, Consider the Hire Assistant problem. We interview...

Consider the Hire Assistant problem. We interview n candidates and always hire the best qualified so far. Let n = 5 for our example. Find the probabilities that we hire exactly 1 t

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