NPAR error

[zhigangmei]

Hi,

I tried to calculate force constant using VASP 5.2 by setting IBRION = 8. To speed up the calculation, I also set NPAR=4 (# of nodes used).

Calculation stops at linear response calculation, and show error message:
---

Linear response DOF= 2
Linear response progress:
Degree of freedom: 1/ 2

-----------------------------------------------------------------------------
| |
| EEEEEEE RRRRRR RRRRRR OOOOOOO RRRRRR ### ### ### |
| E R R R R O O R R ### ### ### |
| E R R R R O O R R ### ### ### |
| EEEEE RRRRRR RRRRRR O O RRRRRR # # # |
| E R R R R O O R R |
| E R R R R O O R R ### ### ### |
| EEEEEEE R R R R OOOOOOO R R ### ### ### |
| |
| VASP internal routines have requested a change of the k-point set. |
| Unfortunately this is only possible if NPAR=number of nodes. |
| Please remove the tag NPAR from the INCAR file and restart the |
| calculations. |
| |
| ----> I REFUSE TO CONTINUE WITH THIS SICK JOB ..., BYE!!! <---- |
| |
-----------------------------------------------------------------------------

After I removed NPAR setting from INCAR, vasp calculation cannot start with error message:

mpirun noticed that process rank 20 with PID 6571 on node n23 exited on signal 11 (Segmentation fault).

This version of vasp is compiled by openmpi with intel mkl library.

I will appreciate if anyone can give some suggestions.


Zhi-Gang

[zhigangmei]

Forgot to mention, the above calculation can run successfully in login node with or without setting NPAR. I am confused where the error comes from.

Zhi-Gang

[alex]

Looks like something weird. I'd suggest to try (a) half and (b) double number of nodes. Sometimes this helps.
NPAR has to be removed from INCAR as you've already figured out.

Good luck!

alex