Parallel.For executes a for loop in which iterations may run in parallel to each other.
Parallel.For executes a for loop in which iterations may run in parallel to each other.
Questions tagged [parallel-for]
98 questions
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static structure array openmp parallel for
I have C code structured like below:
typedef struct
{
double diam;
double more_values;
other_struct other_structures;
...
}ant_struct;
and a static declaration below:
static ant_struct ant[MAX_NUM_ANTENNAS];
I have another section…
David Carey
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Error when using tbb::parallel_for
I'm having an error when I'm using parallel_for of the TBB library. I can't understand why..
I have been able to use tbb::atomic so i'm guessing this in not a linking problem.
Here is the part of my code where i use tbb :
auto values =…
tony497
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parallel openMP loop in cpp
I am trying to learn parallelization with openMP in cpp. I am using the following test example
#pragma parallel for num_threads( 4 )
for ( int i = 0 ; i < N ; i++ ){
for ( int j = 0 ; j < 100000 ; j++ ){
data[ i ] = data[ i ] + (…
zodiac
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2 answers
C++: how can I use parallel-for macro multiple times in same scope?
I'm using a local function definition to run a code block N times acting like a parallel-for version of C# but it gives multiple definition error for f function when I use two or more of it in same scope. How can I make the function name…
huseyin tugrul buyukisik
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1 answer
Does tbb::parallel_for always utilize the calling thread
I have a piece of code where I am using tbb::parallel_for to multithread a loop, which is called by main thread. In that loop I need main thread to update the UI to reflect the progress. From what I have observed, tbb::parallel_for always uses the…
Serge
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C# Parallel.For and Oracle database access - memory exception
I am working on some code that I would like to access an Oracle database inside of a Parallel.For loop. The loop will run for several minutes, and then result in the error:
"Attempted to read or write protected memory. This is often an
…
tuj
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OpenMp For-Loop Parallelization
I try to parallelize the following piece of code with OpenMP.
#pragma omp parallel for collapse(2)
{
for (int mNdx = 0; mNdx < M; ++mNdx)
{
for (int nNdx = mNdx; nNdx < N; ++nNdx)
{
for (int elemNdx = mNdx;…
QckNdDrt
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Parallel.For() updating properties of an item
Suppose I have a "distinct" list of Persons that I need to update. I would like to use Parallel.For()
method in question:
public void UpdatePerson(Person row){
row.Name = //get from cache and update property
}
VS
public Person…
ShaneKm
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Different thread affinities in Parallel.For Iterations
I need an iteration of a parallel for loop to use 7 cores(or stay away from 1 core) but another iteration to use 8(all) cores and tried below code:
Parallel.For(0,2,i=>{
if(i=0)
Process.GetCurrentProcess().ProcessorAffinity =…
huseyin tugrul buyukisik
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0
votes
1 answer
Common keyword to 'continue' in sequential and parallel for loops
In a sequential for loop, the current iteration can be interrupted by calling continue. Similarly, in a Concurrency::parallel_for loop, the current iteration - which is a thread calling a lambda function - can be interrupted with return.
From time…
mOfl
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Matlab sim command in parfor
I would like to run a Simulink model in a parfor loop on many cores with different data. However, I could not get the sim results when I use parfor whereas I can obtain them while using only for loop.
It simply get [t,u] from workspace1, consider a…
okale
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1 answer
Intel TBB parallel loop thread id
How do I determine thread id in a TBB parallel loop body?
Essentially what I need is per-thread copies of an object so I thought I'd have those in array indexed by thread id.
I'm looking for the portable TBB way of doing this, not OS native…
lsr
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Parallel loop counter in Julia
In Julia, I would like to print out inside a parallel for loop the number of iterations the loop has completed.
Is this a safe way to do so, and/or is there a better way?
a = SharedArray(Int, 10)
counter = SharedArray(Int, 1)
arr = 1:10
tot =…
gozzilli
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OpenMP Parallel for with scheduling in C
I want to run a parallel, scheduled(eg. static/dynamic/guided) for-loop, where each thread has its own set of variables, based on their thread-id. I know that any variable declared within the parallel pragma is private, but I don't want to…
Chris Phillips
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How do I use tbb::parallel_invoke to run large number of tasks in parallel?
My problem similar to producer-consumer problem. For e.g. I need to run 999 producers and 1 consumer in parallel. Basically all 999 producers do the same task.
user2963154
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