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!
Write a note on semaphores
A semaphore is a tool meant for synchronizing multiple processes trying to access a shared variable. That is a semaphore is used to deal with the critical section problem or in other words to evade the race condition. A semaphore S is in fact an integer variable that apart from initialization is accessed only through two standard atomic operations:
*Wait and signal.
The traditional definition of wait in pseudo code is:
wait (S) {
while (S<=0)
; // no-op
S--;
}
The traditional definition of signal in pseudo code is:
signal (S) {
S++;
For each process P,
do {
WAIT
Critical Section
SIGNALS
} while (1);
A semaphore is able to be defined as:
typedef struct {
int value;
struct process *L;
} semphore;
Once more, the wait semaphore operation can be defined as:
void wait (semaphore S) {
S.value--;
if (S.value < 0) {
add this process to S.L;
block();
As well, the signal semaphore operation is able to be defined as:
void signal( semaphore S) {
S.value++;
if (S.value <= 0) {
remove a process P from S.L;
wakeup(P);
Q. What resources are utilized when a thread is created? How do they vary from those used when a process is created? Answer: For the reason that a thread is smaller than a pr
Utility Programs: those programs which are not the essential part of operating system. But they provide different utilities / features to the users e.g. MS-DOS : Fdisk, FORMAT, AT
how do you calculate page faults
How a virtual memory can be implemented? What are the benefits of using virtual memory?
Q. Explain about Spooling? Acronym for simultaneous peripheral operations on line. Spooling denotes to putting jobs in a buffer, a special area in memory or on a disk where
Explain about deadlock prevention? In order for the occurrence of deadlock, the four conditions like mutual exclusion, hold and wait, no pre-emption and circular wait must hap
Define swapping. A process requires being in memory to be executed. Though a process can be swapped temporarily out of memory to a backing store and then brought back into memo
Produce a referenced four page report which describes the possible functionality of the system; similar systems that are out there and different possible approaches to delivering t
GUI - Short for Graphical User Interface a GUI Operating System contains icons and graphics and is commonly navigated by using a computer mouse. Below are some instances of GUI Op
Define what a macro definition consists of
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