[Q-e-developers] FFTXlib

[Carlo Cavazzoni]

Dear QE developers,

in the next couple of days I'm going to commit the new FFTXlib, 
replacing the current FFT modules included in the Modules directory.
FFTXlib is contained into a new directory and does not depend from any
other parts of QE, but preserves all previous functionalities.
>From the point of view of QE kernels, the change are minimal and affect only
- a few "use" statements
- dependencies
- a few lines in the Makefile

In the next months, after the next stable release, we are going to make all FFTXlib subroutines "thread safe" so that they can be used with OpenMP threads or tasks.
 
In the long run the idea is to "taskify" the calls to the FFT subroutines in order to expose an higher degree of concurrency to mask communication latency.
 
Moreover it is my intention to do something similar for the basic linear algebra modules (ptoolkit.f90 etc...): take them out from the Modules directory and put them into a separate self-contained directory


best,
carlo