[gmx-users] Gromacs 4.5.4 MPI

[Mark Abraham]

On 4/30/2011 8:50 AM, Juliette N. wrote:
> Dear experts,
>
> I have successfully installed a normal gromacs 4.5.4 installation on 
> one of my machines.
>
> I have read the Installation Instructions that "As of GROMACS 4.5, 
> threading is supported, so for e.g multi-core workstations, MPI is no 
> longer required."
>
> Does this mean that there is no longer the need to do a second 
> configuration with --enable-mpi?

No, it means that --enable-mpi is not necessary for use of GROMACS in 
parallel on multi-core workstations. Thus, many situations will require it.

> Upon trying to configure using this command:
>
> ./configure --enable-mpi --program-suffix=_mpi
>
> There is an error as below:
>
> checking size of off_t... configure: error: in `/root/gromacs-4.5.4':
> configure: error: cannot compute sizeof (off_t)
> See `config.log' for more details.

That error is found repeatedly in the archives. Your MPI compiler is not 
available and/or configured correctly. See the details in config.log.

Mark