[QE-users] there are process with no planes

[Michal Husak]

I am trying to run QE 6.8 on a supercomputer node with 128 cores ...
I use pure MPI parallelization
Run on 16 and 32 cores works OK ...

Run on 64+ cores ends with following error:

Error in routine fft_type_set (6):
there are processes with no planes. Use pencil decomposition (-pd .true.)

Can anybody explain what it means ?
Is my system to simple to it can not feed all cores ?
Where can I enter the -pd .true. option ?

Michal Husak
UCT Prague