In a process using threads, is there one stack per thread, or one stack per process? Explain. In the final version of the process state model, we have a state “blocked and swapped.” If the goal of blocking a process is to prevent the blocked process from wasting resources, why do not we only have “blocked and swapped”? Why a separate state “blocked”? Explain your answer. Linux systems do not allow all signals to be caught or ignored. Suppose they did; how would you stop an application that has ignored all signals from running? Assume at time 5, no system resources are being used except the processor and memory. Given this, consider this sequence of events: at time = 5: P1 executes a command to read from disk unit 3; at time = 15: P5’s time slice expires; at time = 18: P7 executes a command to write to disk unit 3; at time = 20: P3 executes a command to read from disk unit 2; at time = 24: P5 executes a command to write on disk unit 3; at time = 28: P5 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 3, P1’s read is complete; at time = 38: P8 finishes; at time = 40: an interrupt occurs from disk unit 3: P5’s write is complete; at time = 44: P5 is swapped back in; at time = 48: an interrupt occurs from disk unit 3: P7’s write is complete For each of times 22, 37 and 47, identify which state each process is in. If a process is blocked, identify the event on which it is blocked.

In a process using threads, is there one stack per thread, or one stack per process? Explain. In the final version of the process state model, we have a state “blocked and swapped.” If the goal of blocking a process is to prevent the blocked process from wasting resources, why do not we only have “blocked and swapped”? Why a separate state “blocked”? Explain your answer. Linux systems do not allow all signals to be caught or ignored. Suppose they did; how would you stop an application that has ignored all signals from running? Assume at time 5, no system resources are being used except the processor and memory. Given this, consider this sequence of events: at time = 5: P1 executes a command to read from disk unit 3; at time = 15: P5’s time slice expires; at time = 18: P7 executes a command to write to disk unit 3; at time = 20: P3 executes a command to read from disk unit 2; at time = 24: P5 executes a command to write on disk unit 3; at time = 28: P5 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 3, P1’s read is complete; at time = 38: P8 finishes; at time = 40: an interrupt occurs from disk unit 3: P5’s write is complete; at time = 44: P5 is swapped back in; at time = 48: an interrupt occurs from disk unit 3: P7’s write is complete For each of times 22, 37 and 47, identify which state each process is in. If a process is blocked, identify the event on which it is blocked.