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

How many cubic feet of storage space would require, Q. Presume that we agr...

Q. Presume that we agree that 1 kilobyte is 1,024 bytes 1 megabyte is 1,0242 bytes and 1 gigabyte is 1,0243 bytes. This progression carries on through terabytes, petabytes, and ex

What are the advantages of linked allocation, What are the advantages of Li...

What are the advantages of Linked allocation? The benefits are a. No external fragmentation b. Size of the file does not require to be declared

Micro operation, Ask question maxmum words accepted#

Ask question maxmum words accepted#

Explain advantages and inconveniences of ult, ADVANTAGES AND INCONVENIENCES...

ADVANTAGES AND INCONVENIENCES OF ULT Advantages: Thread switching doesn't involve the kernel - no mode switching Scheduling is able to be application specific -

What is page fault, Problem: a) The CPU can access 2 storage devices di...

Problem: a) The CPU can access 2 storage devices directly. What are these 2 storage devices? b) Define 2 key issues involved in memory management. c) How do processes sha

Write a short note on file organization and access, Write a short note on f...

Write a short note on file organization and access. There are three methods to access files 1Record Access 2Sequential Access 3Random Access The record access

Define cpu scheduling, Define CPU scheduling. CPU scheduling is the met...

Define CPU scheduling. CPU scheduling is the method of switching the CPU among several processes. CPU scheduling is the basis of multiprogrammed operating systems. By switching

Information system, using the transformation process model and system think...

using the transformation process model and system thinking concepts explain the key operation of TGL works.

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