Prevention of a data race in a parallelised program, Operating System

Assignment Help:

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;

   }


Related Discussions:- Prevention of a data race in a parallelised program

What are the various available scheme in ipc, Several schemes available are...

Several schemes available are as follows: Pipes : One-way communication process through which different process can interact. The problem is that the two processes could have

What are overlays, What are overlays? To enable a process to be larger ...

What are overlays? To enable a process to be larger than the amount of memory allocated to it, overlays are used. The idea of overlays is to keep in memory only those instructi

Explain the spawnlp functions used in the netware, Explain the Spawnlp Func...

Explain the Spawnlp Functions Used in the NetWare Spawnlp(flags, execName, arg0,...)  The Spawnlp function is used to load  a NetWare executable file (NLM) specified by exec

Explain deadlock prevention, Deadlock Prevention Prevention is the name...

Deadlock Prevention Prevention is the name given to method that guarantee that deadlocks can never happen for the reason that the way the system is structured. Since 4 conditio

Transportation, what are the factors influencing the choice of a mode of tr...

what are the factors influencing the choice of a mode of transportation?

List out the advantages of windows 2000 file management, List out the advan...

List out the advantages of windows 2000 file management. Permits detailed security for individual folders and files. Built-in granular compression capabilities

What are the major differences between operating systems, Q. What are the m...

Q. What are the major differences between operating systems for mainframe computers and personal computers? Answer: In general operating systems for batch systems have simpler

What is the basic approach of page replacement, What is the basic approach ...

What is the basic approach of page replacement? If no frame is free is available, find one that is not presently being used and free it. A frame can be freed by writing its con

Why we need to use a while statement when using wait method, Q. The wait()...

Q. The wait() statement in every Java program examples was part of a while loop. Describe why you would always need to use a while statement when using wait() and why you would ne

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd