parallelize vector array with intelTBB

[pascual__carlos]

Hi, I´m new in IntelTBB and I am trying to parallelize an array of vector. This is the function, in which I pass the array as a pointer.

void calculate(map<int,string> &m, vector<order>* ord, auto&k, string &dir){

for(int i=0;i<k;i++){

   //here I declare a series of variables
   
   for(int j=0; j<ord.size()-1; j++){

        // here I do a series of calculations with the values of 
        // the array and I generate one file for each row of the array
        // with this calculations, to do this I declare more variables
   }


}


}

I want to parallelize this function so that it can process several rows of the array at the same time. I have tried to do this with parallel_for as follows:

void calculate(map<int,string> &m, vector<order>* ord, auto&k, string &dir){


tbb::parallel_for(tbb::blocked_range<int>(0,k),[&](tbb::blocked_range<int> r)
{

for(int i=r.begin(); ;i<r.end();i++){

   //here I declare a series of variables
   
   for(int j=0; j<ord.size()-1; j++){

        // here I do a series of calculations with the values of 
        // the array and I generate one file for each row of the array
        // with this calculations, to do this I declare more variables
   }


}
});


}

This program compile well, but when it is executed, sometimes I obtain one result (generate text file that I need) with wrong calculations, but normally  I obtain an error like this: 

TBB Warning : Exact exception propagation is requested by application but the linked library i
is built without support for it
terminate called after throwing an instance of 'tbb::capture_exception'

I don´t know if this formis the correct form to do it. Can anybody help me?.

Thank you!

[Alexei_K_Intel]

Hi,

Looks like there are at least two issues:

• The application is built with C++11/14 (or newer) compiler options. However, the TBB library is taken from a wrong directory. Do you have a Linux-based system?
• The algorithm throws an exception during parallel processing but this exception is not handled properly and the application terminates.

Regards,
Alex

[pascual__carlos]

Hi Alex,

I am using Oracle VM Virtual Box with Ubuntu 16.04, and I compile as follows:

g++ -std=c++14 p1.cpp -ltbb

I checked the execution of another simpler example and it worked well with Intel TBB. I guess the problem is in parallelizing my application, but I am not sure.

 Is it possible to parallelize this function that I have?

Thank you Alex!

Regards.