Chapter 1

Question 1

What does multiple threads make up?

Answer 1

Processes

Question 2

What 2 methods are there for providing mutual exclusion?

Answer 2

Can and Flags

Question 3

What is Mutual Exclusion?

Answer 3

Separate Threads from accessing CS at the same time

Question 4

What is the liveness property

Answer 4

Something good will happen eventually

Question 5

Why wont the Message-passing work?

Answer 5

Recipient might not be listening/there at all

Question 6

Problem with Can Protocol

Answer 6

Cans cannot be reused so you will run out of memory

Question 7

Problem with Flags (without locks)

Answer 7

If both raise their flags at the same time it could lead to deadlock

Question 8

Is the flag protocol (with defer) Deadlock and Starvation free?

Answer 8

No. It is deadlock free but The one that is being deferred might never get a chance with the CS.

Question 9

Is the flag protocol fair and does it use waiting?

Answer 9

Unfair + waiting

Question 10

Does the Can method work for Producer/Consumer?

Answer 10

Yes

Question 11

What is the bounded buffer problem?

Answer 11

2 processes share common fixed-size buffer. Dont add if full. Dont remove if empty

Question 12

What is the problem with waiting?

Answer 12

If one is delayed everyone is delayed. delays are common & unpredictable

Question 13

Does upgrading from uniprocessor to a n-way MP increase performance linearly?

Answer 13

No

Question 14

Amdahls Law Equation:

Answer 14

s = 1/(1-p +(p/n))