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

Define the term operating system, Question: a) Define the term ‘Operat...

Question: a) Define the term ‘Operating System' and identify two goals of an operating system. b) What do you understand by Symmetric multiprocessing (SMP) and Asymmetr

Modern os, importance of Operating system in modern computers. Also explain...

importance of Operating system in modern computers. Also explain various functions & types of operating systems

Deadlock-avoidance safety algorithm, Q. Presume that you have coded the de...

Q. Presume that you have coded the deadlock-avoidance safety algorithm as well as now have been asked to implement the deadlock-detection algorithm. Can you do thus by simply usin

Explain secondary-storage management, What are the three main activities of...

What are the three main activities of an operating system in regard to secondary-storage management? a) Free-space management. b) Storage allocation. c) Disk scheduling.

Operating system components, Question 1 Discuss the following with respect ...

Question 1 Discuss the following with respect to Operating Systems: Operating System Components Operating System Services Question 2 Describe the theory behind Pagin

What is co-operating scheduling?, What is co-operating scheduling? CPU ...

What is co-operating scheduling? CPU scheduling decisions may possibly place under the following four circumstances: 1.      When process switches from the running state to

Explain doscreatethread functions used in the os/2, Explain DosCreateThread...

Explain DosCreateThread Functions Used in the OS/2  DosCreateThread(&threadID,MyThreadFunction,arg,flags,stackSize) DosCreateThread creates a thread within the context of th

Explain the resource ownership and control, Explain the Resource Ownership ...

Explain the Resource Ownership and Control Operating systems are required to handle many different types of resources. CPU , memory, and I/O devices  are some of the varied sys

Major advantage of the layered approach to system design, Q. What is the ma...

Q. What is the major advantage of the layered approach to system design? What are the de-merits of using the layered approach? Answer: As in all cases of modular design as well

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