[gmx-users] Is openmp necessary?

[Mark Abraham]

On 9/12/2011 7:48 PM, Hsin-Lin Chiang wrote:
> Hi,
>
> For mdrun, the option -nt means "Number of threads to start (0 is 
> guess)".
> Is this option executed by openmp?
> I used this option every time.
> But today my technology stuff told me that we don't have openmp 
> installed in our computer.
> It make me confused.
> Why can I compile and run mdrun -nt 12 before?

mdrun does not use OpenMP at all. -nt creates standard threads, for 
which the best performance will normally be one per physical core, which 
will be auto-detected if you don't specify -nt.

Mark