Very slow. How to move the threads creation to main_?
0
$begingroup$
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
double funcPar()
{
double sum = { 0, 0, 0, 0 };
#pragma omp parallel
{
#pragma omp for
for (int i = 0; i < 4; i++) //loop body should be parallel (multy-threaded)
{
auto a = (double)i;
sum[i] += sin(a)*cos(a); // real code is more complicated and works much longer
}
}//omp parallel
return sum[0] + sum[1] + sum[2] + sum[3];
}
double funcSerial() //function should remain serial (single-threaded)
{
int K = 5000;
double sum = 0.0;
for (int k = 0; k < K; k++)
{
sum += funcPar();
}
return sum;
}
void main_() // //function body should remain serial (single-threaded)
{
int J = 1000;
double sum = 0.0;
for (int j = 0; j < J; j++)
{
sum += funcSerial();
}
printf("nn sum = %f n", sum);
}
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
c++ openmp
asked 36 mins ago
Джон ДоуДжон Доу
1
New contributor
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$endgroup$
add a comment |
0
$begingroup$
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
double funcPar()
{
double sum = { 0, 0, 0, 0 };
#pragma omp parallel
{
#pragma omp for
for (int i = 0; i < 4; i++) //loop body should be parallel (multy-threaded)
{
auto a = (double)i;
sum[i] += sin(a)*cos(a); // real code is more complicated and works much longer
}
}//omp parallel
return sum[0] + sum[1] + sum[2] + sum[3];
}
double funcSerial() //function should remain serial (single-threaded)
{
int K = 5000;
double sum = 0.0;
for (int k = 0; k < K; k++)
{
sum += funcPar();
}
return sum;
}
void main_() // //function body should remain serial (single-threaded)
{
int J = 1000;
double sum = 0.0;
for (int j = 0; j < J; j++)
{
sum += funcSerial();
}
printf("nn sum = %f n", sum);
}
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
c++ openmp
asked 36 mins ago
Джон ДоуДжон Доу
1
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
0
0
0
$begingroup$
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
double funcPar()
{
double sum = { 0, 0, 0, 0 };
#pragma omp parallel
{
#pragma omp for
for (int i = 0; i < 4; i++) //loop body should be parallel (multy-threaded)
{
auto a = (double)i;
sum[i] += sin(a)*cos(a); // real code is more complicated and works much longer
}
}//omp parallel
return sum[0] + sum[1] + sum[2] + sum[3];
}
double funcSerial() //function should remain serial (single-threaded)
{
int K = 5000;
double sum = 0.0;
for (int k = 0; k < K; k++)
{
sum += funcPar();
}
return sum;
}
void main_() // //function body should remain serial (single-threaded)
{
int J = 1000;
double sum = 0.0;
for (int j = 0; j < J; j++)
{
sum += funcSerial();
}
printf("nn sum = %f n", sum);
}
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
c++ openmp
asked 36 mins ago
Джон ДоуДжон Доу
1
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
double funcPar()
{
double sum = { 0, 0, 0, 0 };
#pragma omp parallel
{
#pragma omp for
for (int i = 0; i < 4; i++) //loop body should be parallel (multy-threaded)
{
auto a = (double)i;
sum[i] += sin(a)*cos(a); // real code is more complicated and works much longer
}
}//omp parallel
return sum[0] + sum[1] + sum[2] + sum[3];
}
double funcSerial() //function should remain serial (single-threaded)
{
int K = 5000;
double sum = 0.0;
for (int k = 0; k < K; k++)
{
sum += funcPar();
}
return sum;
}
void main_() // //function body should remain serial (single-threaded)
{
int J = 1000;
double sum = 0.0;
for (int j = 0; j < J; j++)
{
sum += funcSerial();
}
printf("nn sum = %f n", sum);
}
Fully workable code. Very slow. How to move the threads creation to main_ ? Do not break the structure of the code.
c++ openmp
c++ openmp
asked 36 mins ago
Джон ДоуДжон Доу
1
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 36 mins ago
Джон ДоуДжон Доу
1
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 36 mins ago
Джон ДоуДжон Доу
1
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 36 mins ago
Джон ДоуДжон Доу
1
asked 36 mins ago
Джон ДоуДжон Доу
1
1
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Джон Доу is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
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