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

Allocating new pages, Processes have valid and invalid entries on their pag...

Processes have valid and invalid entries on their page tables. The valid entries all point to some where "real" (e.g. a physical page, or some portion of disk in case of non-reside

Define ufd and mfd, Define UFD and MFD. In the two-level directory stru...

Define UFD and MFD. In the two-level directory structure, every user has her own user file directory (UFD). Every UFD has a similar structure, but lists only the files of a one

Thread, advantages and disadvantages of kernal level thread

advantages and disadvantages of kernal level thread

Three conditions that solution for critical section problem, What are three...

What are three conditions that a solution for the critical section problem must satisfy? The three conditions are as following:- a)      Mutual exclusion :- if a process is

What is the use of boot block, What is the use of boot block? For a com...

What is the use of boot block? For a computer to begin running when powered up or rebooted it requires having an initial program to run. This bootstrap program tends to be easy

What is long-term, What is long-term, medium-term, short-term? In a bat...

What is long-term, medium-term, short-term? In a batch system many processes are submitted than are able to be executed immediately. These processes are reel to a mass storage

Define abbreviation of sstf, SSTF stands for Abbreviation of SSTF is S...

SSTF stands for Abbreviation of SSTF is Shortest-Seek-time-first scheduling

Requirements to satisfied by the critical section problem, What are the req...

What are the requirements to be satisfied by the critical section problem? Following are the necessities to be satisfied by the critical section problem: a)      Mutual exc

Direct memory access, A-  In a table format, compare between Programmed I/O...

A-  In a table format, compare between Programmed I/O, Interrupt -driven I/O, and Direct Memory Access (DMA) in terms of basic idea, Advantages, disadvantages, and the operating en

Independent process, what is independent process? distinguished between ind...

what is independent process? distinguished between independent process and co-operating process

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