Final answer:
Priority inversion occurs when a lower-priority task holds a resource that a higher-priority task requires, causing the higher-priority task to wait. It can disrupt the timely execution of critical tasks in real-time systems. Techniques like priority inheritance and priority ceiling protocols help mitigate this issue.
Step-by-step explanation:
This phenomenon is known as priority inversion. It occurs when a lower-priority task holds a resource that a higher-priority task requires, causing the higher-priority task to wait. In computer systems, this can happen when the lower-priority task has access to a shared resource, such as a mutex or a semaphore, and the higher-priority task needs to acquire that resource in order to proceed.
For example, imagine a computer program with three tasks: A, B, and C. Task A has the highest priority, followed by task B, and task C has the lowest priority. Task A needs to access a shared resource that is currently being used by task B. As a result, task A has to wait for task B to release the resource, even though it has a higher priority. This delay in execution is called priority inversion.
Priority inversion can have negative effects on real-time systems, as it can disrupt the timely execution of critical tasks. To mitigate this issue, various techniques, such as priority inheritance and priority ceiling protocols, have been developed to prevent or minimize the occurrence of priority inversion.