[gmx-users] Problem in extending simulation with state.cpt while changing number of cores

Bappa Ghosh ab54741 at gmail.com
Mon Mar 10 17:23:27 CET 2014

Hello all,

I was simulating a mixture of water and carbon-di-oxide for 20ns in one
node with 32 cores. After completion of 20ns run' I extended it for further
15ns with  tpbconv as follows-

tpbconv -s 20ns_old.tpr -extend 15000 -o 15ns_new.tpr -cpi state.cpt
mdrun -s 15ns_new.tpr -o last_15ns.trr

The last 15ns run was carried out in one node with 12 cores.
When I plot coulomb potential energy (short range) for whole 35ns
trajectory, I observe a sharp rise at the extention time (i.e at the
begining of last 15ns run). This sharp rise is not observed if the number
of cores are kept same during extension.

Any comments/suggestions on this observation will be beneficial to me.

Thanks in advance.

Bappa Ghosh
Project Student
C/O -Dr Sudip Roy
CSIR-National Chemical Laboratory,

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