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!
Consider a large web-based database. In some sense, Google is sort of like this. There might be many users who want to read from the database, but only a few users who are allowed to write to the database. If we use standard locks to control access to the database, the application will be much slower than it could be with a more clever type of lock.
Suppose we have one object that is shared among several threads. Suppose also that each thread is either a reader or a writer. Readers only read data but never modify it, while writers read and modify data. If we know which threads are reading and which ones are writing, what can we do to increase concurrency?
First, we have to prevent two writers from writing at the same time. In addition, a reader cannot read while a writer is writing. There is no problem, however in allowing lots of readers to read at the same time. Read-write locks achieve this, and can greatly improve performance for this sort of application.
Note that the lock is the same for both readers andwriters (called 'rw' in the slides), but the readers use an rlock() on the lock and writers use a wlock() on the same lock. Writers requesting a wlock() will have to wait until all readers and writers have released the lock. Readers requesting a rlock() can acquire it even if other readers are holding the lock. Readers however will still have to wait until any writer holding the lock releases the lock.
Demand paging With demand paging, a page is called into memory only when a location on that page is actually indexed during run time. With pre-paging, pages other than the one
Q. If each the access rights to an object are deleted the object can no longer be accessed. At this stage the object should also be deleted and the space it occupies should be ret
Cold Backup: It is copying the three groups of files when the object is shut down. This is a straight file copy, generally from the storage disk directly to tape. You must end th
Task 1 description: Design and implement the disableuser.sh script. Required script functionality: disableuser.sh -v : prints the script version number and exits dis
List the Coffman's conditions that lead to a deadlock. Mutual Exclusion : Only one process might be use a critical resource at a time. Hold & Wait: A process may be alloc
What is an I/O subsystem? The control of devices connected to the computer is a main issue while designing operating systems. Since I/O devices differ widely in their function
What are the steps followed in testing? i. Unit testing - The individual components are tested in this type of testing. ii. Module testing - Related collection of independen
Question 1 Explain the structure of operating system in detail Question 2 Explain the following scheduling algorithm 1) First come Firs
Examining the write/cycles as shown below We can see that the bus is designed for asynchronous read/write cycles. The operation of the write cycle is simple in that the add
Write note on process, process state? A process is in excess of the program code which is sometimes known as text section. It as well includes the current activity as represent
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