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

List disadvantages of using a single directory, List disadvantages of using...

List disadvantages of using a single directory. Users have no privacy. Users must be careful in choosing file names, to avoid names used by others. Users may destroy each othe

Explain the advantage of assembly language, Explain the Advantage of Assemb...

Explain the Advantage of Assembly Language The advantages of assembly language program is: a)    Reduced errors  b)    Faster translation times  c)    Changes could be ma

What are scheduling queues?, What are scheduling queues? Since the proc...

What are scheduling queues? Since the processes enter the system they are put into job queue. This queue contains all processes in the system. The processes that are exist in m

Least-recently used, LRU evicts the page which was last accessed the farthe...

LRU evicts the page which was last accessed the farthest into the past of any page resident in physical memory, i.e. the least-recently used page. LRU approximates OPT when the rec

What is a resource-allocation graph, What is a resource-allocation graph? ...

What is a resource-allocation graph? Deadlocks can be explained more precisely in terms of a directed graph called a system resource allocation graph. This graph having of a se

Android application development using java, This is a group project as desc...

This is a group project as described in the 'AssignmentDescription.pdf' file. I am doing a sub project which is "sub project Mobile application. Android or Apple based. Turn based

Network operating system and a distributed operating system, Problem: (...

Problem: (a) (i) Explain what a single system image is and how it is related to the concept of a distributed operating system? (ii) What are the main differences between a

Operation management, #question After working for 30 years, Ramjee Somjee D...

#question After working for 30 years, Ramjee Somjee Dutt opted for VRS and started a courier company and did very well in the first four years. He was now looking for expansion of

Define deadlock prevention, Define deadlock prevention. Deadlock preve...

Define deadlock prevention. Deadlock prevention is a set of process for ensuring that at least one of the four essential conditions like mutual exclusion, hold and wait, no pr

Define some language processors, Define Name of some language processors?  ...

Define Name of some language processors?   Name of some language processors are as follow: Assembler, Compiler and Interpreter

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