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!
How could we implement locks? No matter how we choose to implement them, we must have some hardware support. One possibility for implementing locks on a uniprocessor machine is is to disable interrupts when testing/setting locks. With interrupts disabled on a single processor machine, the processor cannot switch processes, and so we can guarantee that only the active process will have access to the shared data. Another option would be to make use of atomic operations, such as test and set. This type of operation (which usually corresponds to a single atomic assembly instruction) behaves as if it used the following C function, atomically:
int test_and_set(int x) // let x be strictly either 0 or 1.{if (x) { return 1; } else { x=1; return 0; }}
All this needs to be implemented atomically, in hardware. Using this type of atomic operation, one could implement thread lock(l) simply as while test_and_set(l) {
; // do nothing} // spinlock version of thread_lock()and thread unlock(l) simply asl = 0; // we need this to be an atomic clear (or assign) instruction
The assembly instruction test and set can bemade to be atomic acrossmultiple processors. An equivalent option would be an atomic compare and swap assembly instruction. These low-level hardware solutions are then built up into high-level functions, either built into the languages, or in libraries. In general, do not implement your own locking functions, but rather use functions from a tested library. Getting things right can be tricky, and your own solution is also likely to be non-portable.
What is an operating system? An operating system is a program that acts as a mediator between a user and the computer hardware. The function of an operating system is to provid
Q. How would utilize of a RAM disk affect your selection of a disk-scheduling algorithm? What factors would you require to consider? Do the similar considerations apply to hard-di
When we download a movie from the Internet, we don't care about, say, packet sizes. However, even ifwe are not aware of howlow-level details of networks are implemented, our data i
LINUX OPERATING SYSTEM 1. Write a brief explanation about the Linux distribution. 2. Explain the features that Bash shell provides? 3. Who is responsible for managing use
Use and overview? Pure and impure interpreter?
Question 1: (a) Discuss about the evolution of operating systems from mainframe batch systems to mainframe time sharing systems. (b) Explain your understanding of the "sus
Explain external fragmentation? External fragmentation is the process where the free space and the space still available for use, in a piece of storage become separated into ma
We have talked about blocking locks, which voluntarily yield, and spinlocks, which just spin until they acquire the lock. At ?rst, it seems like spinlocks are verywasteful, and tha
What is an operating system? An operating system is a program that manages the computer hardware. It acts as an intermediate among users of a computer and the computer hardware
explain simple segmentation
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