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.
We can view an operating system as a resource allocator. Explain. We can outlook an operating system as a resource allocator. A computer system has Many resources (software and
In which page replacement policy Balady’s anomaly occurs? FIFO (First in First Out)
Describe Three major roles of operating systems in business computer systems
Processes and threads each have their place in multi-programming, generally to hide latency and to maximize CPU utilization. With the continuing spread of multi-core processors in
In a multiprogramming and time sharing environment several users share the system simultaneously .what are two such problems?
What are threads? A thread - sometimes called as an implementation context or a lightweight process - is a single sequential flow of control within a program. We use threads
Explain the BeginThread Function used in the NetWare example code BeginThread(MyThread Function, stack,size, arg) BeginThread creates a thread and places it on the NetWar
Q. Regard as a logical address space of eight pages of 1024 words every mapped onto a physical memory of 32 frames. a. How several bits are there in the logical address? b. H
What do you understand by “line balancing”? What happens if balance doesn’t exist?
Since each thread has its own processing space therefore communication between threads will need to be done through a common global variable. Since multiple threads can access the
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