1. Quiz Questions Parallel Programming MPI
ITCS 4/5145 Parallel Programming, UNC-Charlotte, B. Wilkinson, 2013, QuizQuestions2a.ppt Sept 19, 2013

2. What is the name of the default MPI communicator?
DEF_MPI_COMM_WORLD
It has no name.
DEFAULT_COMMUNICATOR
COMM_WORLD
MPI_COMM_WORLD

3. What does the MPI routine MPI_Comm_rank() do?
It compares the supplied process ID with that of the process and returns TRUE or FALSE.
It returns an integer that is number of processes in the specifed communicator. The number is returned as an agument.
It converts the Linux process ID to a unique integer from zero onwards.
It returns an integer that is the rank of the process in the specifed communicator. The integer is returned as an agument.
It returns the priority number of the process from highest (0) downwards.

4. What is the purpose of a message tag in MPI?
To provide a mechanism to differentiate between message-passing routines written by different programmers
To count the number of characters in a message
To indicate the type of message
To provide a matching mechanism differentiating between message sent from one process to another process

5. When does the MPI routine MPI_Recv() return?
After the arrival of the message the routine is waiting for but before the data has been collected.
Never
Immediately
After a time specified in the routine.
After the arrival of message the routine is waiting for and the data collected.

6. What is meant by a blocking message passing routine in MPI?
The routine returns when all the local actions are complete but the message transfer may not have completed.
The routine returns immediately but the message transfer may not have completed.
The routine returns when the message transfer has completed.
The routine blocks all actions on other processes until it has completed its actions.
None of the other answers.

7. In the routine: MPI_Send(message,13,MPICHAR,x,10, MPI_COMM_WORLD); when can x be altered without affecting the message being transferred?
Never.
After the routine returns, i.e. in subsequent statements
Anytime
When the message has been received
None of the other answers

8. What does the routine MPI_Wtime() do?
Waits a specific time before returning as given by an argument.
Returns the elapsed time from some point in the past, in seconds.
Returns the elapsed time from the beginning of the program execution, in seconds.
Returns the time of the process execution.
Returned the actual time of day
None of the other answers.