Scheduling -- It's a Process

1. Why are spinlocks inapproriate for single processor systems yet are often used for multiprocessor systems?
   
   
2. In a log based system that provides support for transactions, updates to data items cannot be performed before the coresponding entries are logged. Why is this restriction necessary?
   
   
3. What is mutual exclusion?
   
   
4. In process scheduling, what is aging?
   
   
5. About how long does it take to context switch from one process to another?
   a few machine instructions
   a few hundred machine instructions
   a few milliseconds
   A few seconds
   
   
6. Do real time schedulers use preemption?
   Yes, they normally can and do
   No, they typically should not
   
   
7. What can cause a process to lose the CPU. Choose all the apply.
   Doing I/O
   Doing floating point math
   Executing an illegal instrcution
   Executing the trap instrcution
   Accessing the process stack
   All of the above
   
   
8. Who is the current leading Republican candidate for president?
   
   
9. Among these choices, which typically happens first when doing a context switch?
   Jump to the new process
   Save the stack of the old process
   Decide which process should run next
   
   
10. What does "atomic" mean?
    
    
11. Consider round robin scheduling. What happens if you put two copies of a single process into the round robin queue?
    
    
12. Which will typically be given a higher priority, a low priority real time task or a high priority non-real-time task?
    
    
13. If a process gets the CPU and does computation, how long will it be allowed to keep the CPU before the CPU is taken away?
    A few machine instructions
    A few hundred machine instructions
    A few milliseconds
    A few seconds
    
    
14. Andy says Euclid uses round robin without preemption. He's wrong (he's always wrong). But how can you prove he's wrong.
    
    
15. Who is the current Democratic candidate for president?
    
    
16. For the processess below, can these deadlines be met?
    
    
17. For the processess below, what process is running at timeslice 8 for shortest job next with premeption?
    
    
18. For the processess below, what process is running at timeslice 8 for round robin?
    
    

ProcID	ArrivalTime	Time Needed	Deadline	Priority
1	2		1		3		1 (highest)
2	1		1		999		3
3	4		5		9		2
4	5		4		10		4 (lowest)