An operating system addresses deadlocks through four main strategies: prevention, avoidance, detection, and recovery.

Deadlocks occur when two or more processes cannot proceed because each one is waiting for the other to release a resource. To effectively manage this situation, operating systems employ various strategies.

The first strategy is deadlock prevention, which aims to ensure that at least one of the necessary conditions for a deadlock does not hold. This can be accomplished by implementing policies that disrupt one or more of the following conditions: mutual exclusion, hold and wait, no preemption, or circular wait.

Another approach is deadlock avoidance, which necessitates that the operating system has prior knowledge about which resources will be requested and when they will be released. Based on this information, the system makes decisions to prevent potential deadlocks. A common implementation of this strategy is the Banker’s algorithm, which simulates resource allocation for each process and checks whether the allocation would lead to a safe state (no deadlock) or an unsafe state (potential deadlock).

Deadlock detection takes a more reactive stance, where the operating system periodically checks for deadlocks, often using a resource allocation graph. If a cycle is identified within the graph, it indicates the presence of a deadlock. However, this method can be resource-intensive and may degrade system performance, especially in larger systems with numerous processes and resources.

Finally, once a deadlock is detected, the system must recover from it. Recovery can be achieved by terminating one or more processes to break the deadlock or by preempting resources from certain processes and reallocating them to others. Both of these recovery methods come with their own challenges: terminating a process can lead to loss of progress, while preempting resources may cause starvation, where a process is indefinitely denied the resources it requires.

In summary, managing deadlocks is a complex challenge that necessitates careful oversight by the operating system. The strategy employed will depend on the specific needs and constraints of the system, and often a combination of these strategies is implemented to effectively handle deadlocks.