Question

Assume that at time 5 no system resources are being used except for the processor and memory. Now consider the following events:

At time 5: P1 executes a command to read from disk unit 1.

At time 15: P2's time slice expires.

At time 18: P4 executes a command to write to disk unit 1

At time 20: P3 executes a command to read from disk unit 2.

At time 24: P2 executes a command to write to disk unit 1

At time 28: P2 is swapped out.

At time 33: An interrupt occurs from disk unit 2: P3's read is complete.

At time 36: An interrupt occurs from disk unit 1: P1's read is complete.

At time 38: P5 terminates.

At time 40: An interrupt occurs from disk unit 1: P2's write is complete.

At time 44: P2 is swapped back in.

At time 48: An interrupt occurs from disk unit 1: P4's write is complete.

For each time 22, 25, 37, and 47, identify which state each process is in. If a process is

blocked, further identify the event on which is it blocked.

Answer 1

1.