Quiz 2
Course: cs241 - System Programming, CS Department
Date: February 10, 2006
Netid: Name:
Note: Completion of quiz is an individual effort. The quiz takes 10 minutes. The student
gets additional 5 points for taking the quiz. Each question has ONLY ONE ANSWER!!!
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1. (1 Point) Threads of the same task have the following characteristics: (I) Share
the same address space, (II) Reduce context switching overhead; (III) Are
protected from each other the same way as processes. Which thread
characteristics are correct?
a. I, II, III
b. I, III
c. I, II
2. (1 Point) If a user process P runs two user-threads, T1(read-thread), and T2
(compute-thread) on top of a multi-threaded kernel, and thread T1 calls ‘read’
instruction, the following happens:
a. user process P will block and another process Q will run
b. thread T1 will block and T2 will run
c. kernel threads will block
Note: Since the binding between user threads and OS threads of the multi-threads
kernel was ambiguous (i.e., both threads of the process P could be bound to one or
two OS threads), we accepted answer (a) as well as a correct anwer.
3. (1 Point) Priority inversion between two processes, one with high priority and
the other with low priority, that share a critical section, will cause the following
problem:
a. high priority process executes before low priority process and finishes
faster than it should
b. low priority process executes before high priority process and finishes
faster than it should
c. high priority process waits for low priority process (that holds the
semaphore) to finish, but the low priority process never gets
scheduled
d. low priority process changes priority temporary to the priority of the high
priority process
4. (1 Point) What is the minimum number of parameters to a ‘message send’
operation?
a. 1
b. 2
c. 3
