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 hierarchical paging method, Hierarchical paging method Most mo...

Hierarchical paging method Most modern computer systems maintain a large logical-address space. In this situation the page table itself turns into excessively large. To remedy

What is the use of FIFOs in client-server applications, What is the use of ...

What is the use of FIFOs in client-server applications

WINDOWS XP, DESIGN GOALS OF WINDOWS XP.DESCRIBE IN DETAIL.

DESIGN GOALS OF WINDOWS XP.DESCRIBE IN DETAIL.

What are the issues in designing a network-transparency, Transparency : ...

Transparency : Users must be able to access remote resources as though these resources were local. Transparency should as well promote user mobility. Users must be allowed to lo

Find the number of drives in the jukebox, Q. In a disk jukebox what would b...

Q. In a disk jukebox what would be the result of having more open files than the number of drives in the jukebox? Answer: Two bad results could result. One likelihood is star

What is a process control block?, What is a Process Control Block? Ever...

What is a Process Control Block? Every process in the operating system is represented by a process control block as well called a task control block. It contains several pieces

What effect would updating a few byte on the one page, Q. What is the effe...

Q. What is the effect of permitting two entries in a page table to point to the same page frame in memory? Describe how this effect could be used to decrease the amount of time ne

Explanation of computer clustering and benefits, The CTO is still impressed...

The CTO is still impressed with your work. He just came back from a technology exposition where he heard about computer clusters. All he knows is that they are the big thing for bu

Explain the grouping threads that execute similar functions, Grouping Threa...

Grouping Threads That Execute Similar Functions   Thread Groups are generally used to group threads that execute similar functions of the application program. For instance, if

Explain the file-system manipulation, Q. Explain the File-system manipulati...

Q. Explain the File-system manipulation? File-system manipulation there is several details in file allocation, creation, deletion and naming that users should not have to perfo

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