[gmx-users] Error using double precision

[David van der Spoel]

edvin.erdtman at nat.oru.se wrote:
> I installed both double and single precision gromacs on a new system. When running a membrane MD with double precision 8 processor mpi calc, this error appars in the error output file:
> 

this usually means you have an unequilibrated system.


> Error on node 4, will try to stop all the nodes
> Halting parallel program mdrun_mpi_d-0(mpi:17347 at n182) on CPU 4 out of 8
> -------------------------------------------------------
> Program mdrun_mpi_d-0(mpi:17347 at n182), VERSION 3.3.1
> Source code file: nsgrid.c, line: 226
> 
> Range checking error:
> Explanation: During neighborsearching, we assign each particle to a grid
> based on its coordinates. If your system contains collisions or parameter
> errors that give particles very high velocities you might end up with some
> coordinates being +-Infinity or NaN (not-a-number). Obviously, we cannot
> put these on a grid, so this is usually where we detect those errors.
> Make sure your system is properly energy-minimized and that the potential
> energy seems reasonable before trying again.
> 
> Variable ci has value 1335. It should have been within [ 0 .. 1296 ]
> Please report this to the mailing list (gmx-users at gromacs.org)
> -------------------------------------------------------
> 
> Thanx for Using GROMACS - Have a Nice Day
> 
> Error on node 6, will try to stop all the nodes
> 
> Halting parallel program mdrun_mpi_d-0(mpi:17347 at n182) on CPU 6 out of 8
> gcq#10922: Thanx for Using GROMACS - Have a Nice Day
> 
> ***** MPI-error in rank 2 Routine MPI_Abort : Terminating after call to MPI_Abort *****
> --- mpimon --- Aborting run after process-2 terminated abnormally Childprocess 17353 exited with exitcode 2 ---
> 
> gcq#10922: Thanx for Using GROMACS - Have a Nice Day
> 
> 
> Thankful for some help.
> Edvin
> 


-- 
David van der Spoel, Ph.D.
Molec. Biophys. group, Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205. Fax: +4618511755.
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://folding.bmc.uu.se