serial vs parallel

[Sushil Auluck]

hi,

i have been able to compile exciting-code ( lithium) with gfortran

for serial and parallel (mpi only) runs. in parallel i can excitingmpi running

on 4 cores (system has one node with 32 cores). but the cpu

time seems to be more than for a serial run....is it possible that

the excitingmpi is making 4 copies of the serial runs.system has

 Linux sandybridge.iuac.res.in 2.6.32-279.11.1.el6.x86_64 #1 SMP

Tue Oct 16 15:57:10 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

please suggest some ideas.

sushil auluck

[Sushil Auluck]

hi,

please ignore my earlier post. i was using the wrong mpirun....

now all is ok. a serial run took 369s while for -np 4 it was 122s.

s.auluck

[DibyaR Prakash]

Respected Sir

I am extremely sorry to burden you. I have a problem with the calculation of systems with more than one atoms. Suppose I want to investigate a sysyem within GGA in Exciting code for sysytem like Co2VSb. I have no idea how to include spacegroup and lattice parameter in the input.xml file.

Here is the detail of Co2VSb

lattice constant, a=b=c=6.00

ab=ac=bc=90

spacegroup=fm3m

Positions

Co=0.25, 0.25, 0.25

Co=0.75, 0.75,0.75

V=0.5, 0.5,0.5

Sb=0.0, 0.0, 0.0

how does my input file look like?

With regards

D. P. Rai

Mizoram University

India