Intel® oneAPI Math Kernel Library
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Do the MKL FFT Handler creation uses malloc??

shiva_rama_krishna_b
217 Views

Hi,

When we want to use MKL FFT we create a handler for that. So do this handler creation involves malloc system call? If not which method is used to allocate memory.

 

Thanks

sivaramakrishna

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4 Replies
Evgueni_P_Intel
Employee
217 Views

MKL calls the i_malloc callback function which has the same interface as malloc and can be overridden by the user.

shiva_rama_krishna_b
217 Views

Thank you Evgueni Petrov.

what happens If more than one thread calls creation of handler of its own. do they run sequncially or parallel?.

Thanks

sivaramakrishna

Evgueni_P_Intel
Employee
217 Views

MKL does not serialize execution of DftiCreateDescriptor in different application threads.

shiva_rama_krishna_b
217 Views

Hi Evgueni Petrov,

I was trying call FFT by multiple threads at a time. code snippet looks like below. I noticed  [MKLSERVICE]@lock function in vtune profiler. when i pulled the handler creation outside the loop, i did not find [MKLSERVICE]@lock in vtune profiler. This is actually making me to believe that MKL is doing some locking while allocating handler.

#pragma omp parallel num_threads(236)
for(i = 0; i < 236; i++)
{
                          .
                          .
                          .
                       some functions..
                          .
                          .

                      create handler one for each 'i'.
                      Call FFT using 'i'.

}

Thanks

sivaramakrishna

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