Dear LAMMPS developers and users,
in our research group we are using LAMMPS for several long-running
simulations. Since we are running LAMMPS on a public computer cluster which
has a 12 hour wallclock time limit for computing jobs, we have to restart the
simulation several times to reach the desired number of time steps. At the
moment we do this by hand which basically requires the following steps:
1. Look into the log files and determine the last time step at which a restart
file has been written.
2. Write a new LAMMPS script file that loads the last restart file and then
runs for the remaining number of timesteps.
3. Write a new job file for the new LAMMPS script and submit it to the queue.
This procedure is very tedious and it is almost impossible to automate it in
some way. I would like to know from the LAMMPS community if you also consider
this as a problem or if you already have found a solution for it which I have
I would propose to solve this issue by adding a new function to LAMMPS.
Basically, it would be sufficient to add a new mode of operation to LAMMPS
which makes it skip a defined number of timesteps in the input file. That
means it would process all regular commands like fix/compute etc. but not the
run/dump/write commands up to a given number of timesteps. Then it should
somehow load the specified restart file and continue with normal execution.
This would make it unnecessary to write a new LAMMPS input file to continue
an aborted simulation.
I know that this would require some major changes to the LAMMPS code and maybe
no one is willing to do it. But I wanted to call the developers' attention to
this issue and put my proposal up for discussion.