62 Which of the following factors determine the probability that a lock used for mutual exclusion will be unavailable when thread X requests it? (Multiple answers are possible.)
Fraction of processing time that threads spend holding the lock
Number of threads contending for the lock
Whether lock ordering is being used to avoid deadlock
How many milliseconds thread X will need to hold the lock
Whether the lock is implemented with a mutex or a semaphore
72
Which of the following are elements of thread state (vs. process state)? (Multiple answers are possible.)
Location of the heap
scheduling state (running/ready/blocked)
stack location
User Identification
saved general registers
82
Which of the following are limitations of using semaphores for synchronization? (Multiple answers are possible.)
Can't handle multiple threads waiting on the same semaphore
Can't check for mutual exclusion without blocking
Deadlock avoidance approaches using wait-for graphs can't work on semaphores.
Can't use them to solve producer/consumer problems.
Can't support priority allocation among those waiting for a semaphore