Parallel and Distributed Practical Lab Quiz

• OpenMP is:

• A standard for Distributed Programming Model

• A standard for uniprocessor optimization

• A standard for writing parallel applications that supports shared programming model

• All of the above

OpenMP follows fork/join model because

• • 
    

    OpenMP programs start with a single thread

• It initiates with a single thread and further a team of threads is created

• Statements in parallel block are executed in parallel by every thread

• master creates “team of parallel worker”, threads and at end of parallel region, all threads synchronize, and join master thread At start of parallel region

• Barrier synchronizations should be used whenever we want to ensure all threads have completed a common phase of their execution_____________  

• Before any of them start the next phase

• After any of them start the next phase

• Before any of them start the previous phase

• After any of them start the previous phase

• Omp_get_num_threads () environment variable gives:

• Thread ID of all the threads

• Maximum number of threads in a team

• Return number of threads in a team

• None

• Omp_get_thread_num () environment variable gives:

• Maximum number of threads in a team

• Thread ID of the thread

• Both a) and b)

• None

• Consider the following piece of code:#include #include  int main(void){omp_set_num_threads (10);#pragma omp parallel {for (i=0; i<100; i++)printf ("Parallel Processing Quiz.\n");}return 0;} How many times “Parallel Processing Quiz” will get printed? 

• 100 times

• 1000 times

• 10 times

• Can't predict

•  

  If both export OMP_NUM_THREADS and omp_set_num_threads both are used in a program than the threads will be set to launch the parallel section in accordance with-

• Omp_set_num_threads

• OMP_NUM_THREADS

• Whichever sets maximum number of threads

• Whichever sets minimum number of threads

• What is the purpose of using barrier synchronizations in OpenMP?

• To ensure all threads have completed a common phase of their execution before starting the next phase

• To ensure all threads have completed a common phase of their execution after starting the next phase

• To ensure all threads have completed a common phase of their execution before starting the previous phase

• To ensure all threads have completed a common phase of their execution after starting the previous phase

• What does the Omp_get_num_threads() environment variable return in OpenMP?

• Thread ID of all the threads

• Maximum number of threads in a team

• Return number of threads in a team

• None

• Why does OpenMP follow the fork/join model?

• • 
    

    OpenMP programs start with a single thread

• It initiates with a single thread and further a team of threads is created

• Statements in parallel block are executed in parallel by every thread

• Master creates a team of parallel workers, threads, and at the end of the parallel region, all threads synchronize and join the master thread at the start of the parallel region