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hi, Im trying to calculate the vibrational energy of a 2x2x2 supercell of PdH, with 4 4 4 k points.
I get the following error - Vasp internal routines have requested a change of the k-point set. Unfortunally this is only possible if NPAR=number of nodes. Please remove the NPAR tag from the INCAR file and restart the calculation.

I dont have the NPAR tag in my INCAR file. According to OUTCAR, the calc is running on 6144 nodes with one band on 24 nodes, 256 groups.

Im a vasp beginner and not really sure how to fix this. Thanks

INCAR:

SYSTEM = PdH

#Electronic
ISMEAR=1
ISTART=0
SIGMA=0.2
PREC = Normal
ENCUT = 660
EDIFF = 0.00001

#Geometry
NSW = 200
EDIFFG = -0.01
#IBRION = 2
#ISIF = 3

#Vibrational
IBRION = 6
NFREE = 2
POTIM = 0.015


#Output
LWAVE = .TRUE.
LCHARG = .FALSE.

#Dos
#LORBIT = 10
#NEDOS = 200
#EMIN = -10
#EMAX = 10

Well, to make it work you need to set NPAR = 6144 in your INCAR file. But are you really running over 6144 cpu-cores with 1 mpi-rank/core? Sounds like a very broad job for such a system. How do you submit you job? And what does "echo $OMP_NUM_THREADS" give you ?

Cheers,
Dan

Hi Dan, Im running the job on HeCTOR (uk supercomputer), i think ive got it running on 256 nodes with 24 processes on each node, which makes up to 6144.

Im using so many nodes because the calculations wont finish in the allotted 12 hours and im having problems restarting the calculations, if I copy CONTCAR to POSCAR and use ISTART=0 (I have an empty WAVECAR, despite LWAVE=TRUE, but i think this is normal) , the vasp calc stops with an error saying that the k-points have changed. (im probably wrong on this but trying my best to complete calculations using the HeCTOR guide and VASP manual and not a lot else).

I dont get anything back when i echo $OMP_NUM_THREADS, just a blank line

Thanks

<span class='smallblacktext'>[ Edited Sat Aug 13 2011, 09:02PM ]</span>