Consider three concurrent processes P1, P2 and P3 as shown below, which access a shared variable D that has been initialized to 100.
The processes are executed on a uniprocessor system running a time-shared operating system. If the minimum and maximum possible values of D after the three processes have completed execution are X and Y respectively, then the value of Y–X is _________.
Your input ____
2
GATE CSE 2015 Set 1
MCQ (Single Correct Answer)
+1
-0.3
A file is organized so that the ordering of data records is the same as or close to the ordering of data entries in some index. Then that index is called
A
Dense
B
Sparse
C
Clustered
D
Unclustered
3
GATE CSE 2015 Set 1
Numerical
+1
-0
The following two functions P1 and P2 that share a variable B with an initial value of 2 execute concurrently.
P1( ) {
C = B – 1;
B = 2 * C;
}
P2( ) {
D = 2 * B;
B = D - 1;
}
The number of distinct values that B can possibly take after the execution is___________.
Your input ____
4
GATE CSE 2013
MCQ (Single Correct Answer)
+1
-0.3
Three concurrent processes X, Y, and Z execute three different code segments that access and update certain shared variables. Process X executes the P operation (i.e., wait) on semaphores a, b and c; process Y executes the P operation on semaphores b, c and d; process Z executes the P operation on semaphores c, d, and a before entering the respective code segments. After completing the execution of its code segment, each process invokes the V operation (i.e., signal) on its three semaphores. All semaphores are binary semaphores initialized to one. Which one of the following represents a deadlock-free order of invoking the P operations by the processes?
