Least-recently used, Operating System

Assignment Help:

LRU evicts the page which was last accessed the farthest into the past of any page resident in physical memory, i.e. the least-recently used page. LRU approximates OPT when the recent past is a good prediction of the future, which is often true in real programs. Variants of the LRU policy are currently used in all real operating systems. We will discuss LRU further below. For certain patterns of memory accesses, however, LRU can be quite bad. For example, the worst case for LRU is a loop which is larger than the cache size (physical memory size in this case). In this situation, LRU will miss, or page fault, on every page access. So perhaps there are alternatives which are better than LRU?


Related Discussions:- Least-recently used

What are the common strategies to select a free hole, What are the common s...

What are the common strategies to select a free hole from a set of available holes? The most common methods are a. First fit b. Best fit c. Worst fit

What is a process control block?, What is a Process Control Block? Ever...

What is a Process Control Block? Every process in the operating system is represented by a process control block as well called a task control block. It contains several pieces

Perform alpha-beta pruning on the following tree, Perform alpha-beta prunin...

Perform alpha-beta pruning on the following tree. Put an "X" over each node that is pruned. Put the final value next to all other nodes. Indicate which action MAX should take: to B

Define rotational latency and disk bandwidth, Define rotational latency and...

Define rotational latency and disk bandwidth. Rotational latency is the additional time waiting for the disk to rotate the wanted sector to the disk head. The disk bandwidth is

Computer, what is an operating system?

what is an operating system?

Briefly discuss on real-time scheduling, Briefly discuss on real-time sched...

Briefly discuss on real-time scheduling? It is divided into two types.  Hard real-time systems are needed to complete a critical task within a guaranteed amount of time. T

BARBER SHOP PROBLEM, a) The barber shop has one barber, one barber chair, a...

a) The barber shop has one barber, one barber chair, and n chairs for waiting customers, to sit on. If there are no customers present, the barber sits down in the barber chair and

Program, i need the job to be done within 3days

i need the job to be done within 3days

Clocks in distributed systems, Clocks in distributed systems : a. Why ar...

Clocks in distributed systems : a. Why are clocks difficult to synchronize in distributed systems? b. What features in a system assume that the clocks are (reasonably) synchr

Explain and differentiate programmed and interrupt i/o, Question 1 Explain...

Question 1 Explain the structure of operating system in detail Question 2 Explain the following scheduling algorithm                                     1) First come Firs

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