HOMEWORK 6 (COMMENTS AND COMMON MISTAKES)

<< Problem 3 >>

o The algorithm does NOT schedule processes according to the order in which
  they entered the "testing" section.

o When explaining a property of an algorithm, try to get at the core idea(s).
  The core idea in Lamport's Bakery algorithm is that processes get ticket
  numbers which are non-decreasing in value but need not be unique.  Ties
  are broken by choosing the lowest numbered proccess id.

<< Problems 4 and 5 >>

o Ambiguous Receiver

  Many solutions contained something like the following to indicate to a
  customer that it's service was finished:

	Teller Process		Customer Process
	--------------		----------------
	Signal(tDone);  -------> Wait(tDone);

  But because there are two tellers, it is possible that a customer reacts
  to the tDone signal from the incorrect teller.  The solution is to have
  each teller use a different semaphore:

	Teller Process		Customer Process
	-----------------	---------------------
	Signal(tDone[i]);  ---> Wait(tDone[myTeller);

o Many solutions did not explain the purpose of each semaphore.

o Showing the signal-wait pairings would help in exposing dangling signals
  and mutual exclusion problems.