What happens if an attempt to solve the critical section problem does not implement the “progress” requirement?
A. A process will be allowed an unlimited number of consecutive entries to its critical section.
B. A process waiting to enter the critical section may starve.
C. Deadlock is guaranteed.
D. Mutual exclusion is compromised.
The correct answer and explanation is:
The correct answer is B. A process waiting to enter the critical section may starve.
Explanation:
The critical section problem is a fundamental concept in computer science that deals with managing the access of multiple processes to a shared resource (the critical section) without causing conflicts or data inconsistency. For a solution to be considered valid, it must satisfy three key requirements: mutual exclusion, progress, and bounded waiting.
The progress requirement specifies that if no process is currently in its critical section, and if some processes are waiting to enter, the system must guarantee that one of the waiting processes will eventually be allowed to enter the critical section. This ensures that the system continues to function and doesn’t freeze, allowing progress to be made.
If a solution does not meet the progress requirement, it can lead to starvation. Starvation occurs when a process waiting for access to the critical section is never granted the opportunity to enter. This can happen if the scheduling of processes is unfair, for instance, where one process is consistently given preference over others, or if the algorithm allows some processes to continually skip others. As a result, the process that is perpetually denied entry to the critical section may never get a chance to execute its critical tasks, thus leading to starvation.
To avoid this, many synchronization mechanisms (such as semaphores, locks, or monitors) include features that ensure fairness and prevent indefinite blocking of processes. These mechanisms are designed to meet all three requirements of the critical section problem, ensuring both fairness and system efficiency. If the progress requirement is ignored, it undermines the fair scheduling of processes and could result in situations where one or more processes are perpetually blocked from executing their critical operations.