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

Explain a working of file control block, Explain a working of file control ...

Explain a working of file control block A file control block (FCB) has information about the file, containing ownership, permission, and location of the file contents. The log

Activities of operating system-secondary-storage management, Q. What are th...

Q. What are the three main activities of an operating system in regard to secondary-storage management? Answer: 1) Free-space management 2) Storage allocation 3) Disk

Enforce memory protection at compile time?, Why is it not possible to enfor...

Why is it not possible to enforce memory protection at compile time?   Every process should be protected against unwanted interference by other process, whether intentional or

Evolution of operating system, breifly write a note on about evolution of o...

breifly write a note on about evolution of operating system?

Define the tlsfree(tlsindex) function, Define the TlsFree(TLSIndex) Functio...

Define the TlsFree(TLSIndex) Function This function should be called to free a TLSindex allocated by TlsAlloc. It would be executed when there are no more threads in a process

Introduction to paging, We will brie?y introduce paging to ?nish off this l...

We will brie?y introduce paging to ?nish off this lecture. When a process is loaded, not all of the pages are immediately loaded, since it's possible that they will not all be need

Ipc, Explain in detail about ipc in linux

Explain in detail about ipc in linux

Explain working of the logical file system, Explain working of the logical ...

Explain working of the logical file system The logical file system manages metadata information. Metadata contains all of the file-system structure, excluding actual data. It h

Copy on write in virtual memory, how copy on write on pages when many proc...

how copy on write on pages when many process works at a same time?

Business, why some companies do not pay sufficient attention to staff induc...

why some companies do not pay sufficient attention to staff induction

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