Present your own fully documented and tested programming example illustrating the prevention of a data race in a parallelised program.

This is an example where total number of prime number between 2 and 10000 is being calculated. The order of memory accesses is prevented from being non-deterministic and from the code data race is avoided by making it parallelized with OpenMP directives.  The inconsistency can be seen by running the program consecutively for 3 or more times.

 

#include

#include

#include

#define MyThreads 4

#define num 10000

 

   int primeNum[num];

   int primeF[num];

 

   int is_prime(int v)

   {

    int i;

    int lim = floor(sqrt(v)) + 1;

 

    for (i = 2; i < lim; i++) {

           /* no need to check against known composites */

           if (!primeF[i])

               continue;

           if (v % i == 0) {

               primeF[v] = 0;

               return 0;

           }

       }

       return (v > 1);

   }

 

   int main(int argn, char **argv)

   {

       int i;

       int total = 0;

            printf("Enter a number greater than 2");

            scanf("%d", &num)

   #ifdef _OPEnumMP

       omp_set_dynamic(0);

       omp_set_num_threads(MyThreads);

   #endif

 

       for (i = 0; i < num; i++) {

           primeF[i] = 1;

       }

 

       #pragma omp parallel for

       for (i = 2; i < num; i++) {

           if ( is_prime(i) ) {

               primeNum[total] = i;

               total++;

           }

       }

        printf("total prime numbers that lie between 2 and %d: %d\n",

              num, total);

       return 0;

   }

Posted Date: 6/29/2012 2:13:59 AM | Location : United States

Ask an Expert

Related Discussions:- Prevention of a data race in a parallelised program, Assignment Help, Ask Question on Prevention of a data race in a parallelised program, Get Answer, Expert's Help, Prevention of a data race in a parallelised program Discussions

Write discussion on Prevention of a data race in a parallelised program
Your posts are moderated

Write your message here..

Related Questions

Principles of operating systems, Objective - Tiny Shell (tish) In this... Objective - Tiny Shell (tish) In this exercise you will write a small shell program to run different programs in foreground and background mode. Background Usually when

What is meant by the term affinity in processor sheduling, Question: (a... Question: (a) Answer the following questions based on the code snippet below. 1. int main (int argc, char *argv[]) 2. { 3. 4. pid_t processId; 5. 6. processId =

Example of semaphore, For example, by initializing a semaphore to 0, thread... For example, by initializing a semaphore to 0, threads can wait for an event to occur, and impose an ordering constraint, similar to a monitor using condition variables, but with m

EMBEDDED SYSTEM, EXPLAIN EMBEDDED SYSTEM EXPLAIN EMBEDDED SYSTEM

Explain fifo page replacement, FIFO page replacement This is the easie... FIFO page replacement This is the easiest page replacement algorithm. At this juncture the 1 st page entering is the 1 st to leave that is the oldest page leaves. To execute

How is process management done in multiprocessing systems, How is process m... How is process management done in multiprocessing systems ? There are two accost for the process management in multiprocessor systems. Master-slave configuration Sy

Unix script, As a group, you may need to make some enhancements to your dev... As a group, you may need to make some enhancements to your development server (NOT your stable server!)  It needs to be able to run the makepasswd program, which may require instal

Define what a macro definition consists of, Define what a macro definition ... Define what a macro definition consists of

..unbounded buffer, what is unbounded buffer what is unbounded buffer

Critical section, what is deckers algorithm what is deckers algorithm