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.