Quiz Questions ITCS 41455145 Spring 2012 ITCS 45145

Quiz Questions ITCS 4145/5145 Spring 2012 ITCS 4/5145 Parallel Programming, UNC-Charlotte, B. Wilkinson, 2012, Jan 24, 2012

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

What is meant by a non-blocking (or asynchronous) message passing routine in MPI? a) The routine returns when all the local actions are complete but the message transfer may not have completed. b) The routine returns immediately but the message transfer may not have completed. c) The routine returns when the message transfer has completed. d) The routine blocks all actions on other processes until it has completed its actions. e) None of the other answers.

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

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