Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Now, let us discuss two related algorithms for deciding which pages to evict. The clock algorithm is one of the most popular choices. It works by keeping frames in a circular structure. (Note that this circle may be very large: a 32-bit machine with 4k pages can have up to 220 1 million frames.) When a page fault occurs, it checks the reference bit of the next frame. If that bit is zero, it evicts that page and sets its bit to 1; if the reference bit is 1, the algorithm sets the bit to 0 and advances the pointer to next frame.
An implementation which is often used in real operating systems is a segmented queue. This type of algorithm divides all existing pages into two sets of pages. The most-active one-third of all pages use a clock algorithm. After that, pages that are evicted out of the clock are moved to a "uncommon" linked list, in which we use exact LRU. This way, we approximate LRU for the frequently-referenced pages (1/3 of the page frames - fast clock algorithm), and at the same time use exact LRU on the infrequently accessed pages (2/3 of all page frames). Since the pages in the uncommon list are not accessed very frequently, it is okay if their accesses are a little slower due to some pointer manipulation.
Q. What is the major advantage of the layered approach to system design? What are the de-merits of using the layered approach? Answer: As in all cases of modular design as well
#questionThe Fibonacci sequence is the series of numbers 0,1,1,2,3,5,8,… Formally, it can be expressed as: fib0 = 0 fib1 = 1 fibn = fib n-1 + fib n-2 Write a C program u
Write a note about Directory structure with examples. The FreeBSD directory hierarchy is basic to obtaining an overall understanding of the system. The most significan
What are the methods for handling deadlocks ? The technique for handling the deadlocks are: We are able to use protocol to prevent or avoid the deadlock, make sure tha
LINUX VS WINDOWS I/O MANAGEMENT
What is a semaphore? A semaphore 'S' is a synchronization tool which is an integer value that, apart from initialization, is accessed only by two standard atomic operations; w
What lead to the concept of paging? The main memory is separated into two parts that are one for the resident operating system, and one for the user processes. We may perhaps p
Define Maintaining Data on a Per Client Basis Perhaps the most dramatic syntactical programming change for the application developer of client – server applications is maintain
what is file abstraction?
What are the different file operations? Create : - Space for the file in the file system update directory table. Write : - file name and data to be written is
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd