what are some examples of a computer system in an unsafe state and describe how the process could be complete without causing a deadlock.
An example of a computer system in an unsafe state is when multiple processes are competing for shared resources and can potentially enter a deadlock situation. A deadlock occurs when each process is waiting for a resource that is held by another process, resulting in a situation where none of the processes can proceed.
To avoid deadlock and ensure the completion of the process, we can use various techniques like resource allocation strategy, prevention, avoidance, or recovery approaches. Here's an example illustrating how to complete the process without causing a deadlock:
Let's consider a system with two processes, P1 and P2, and two resources, R1 and R2. The following scenario assumes that both processes require both resources to complete their tasks:
1. Initially, P1 acquires resource R1 and P2 acquires resource R2.
2. P1 completes its task using R1, releases it, and requests R2.
3. P2 completes its task using R2, releases it, and requests R1.
4. Instead of blindly granting the requests, a resource allocation strategy can ensure that the requested resource is available before allocation.
5. If resource R2, requested by P1, is not available because P2 is holding it or it is allocated to another process, P1 will wait for it to be released.
6. Similarly, if resource R1, requested by P2, is not available because P1 is holding it or it is allocated to another process, P2 will wait for it to be released.
7. Once the requested resource becomes available, the process can acquire it and continue its execution.
8. This way, both processes can complete their tasks without entering a deadlock state.
By employing proper resource allocation strategies such as resource preemption, priority-based allocation, or using wait-for graphs to detect potential deadlocks, the computer system can maintain a safe state and avoid deadlock scenarios, ensuring completion of processes without interruptions.