Separate PME ranks are not assigned since e87a53
Since the new task assignment code was commited, Gromacs no longer assigns separate PME ranks when running on 80 hardware threads (dev-purley02).
Instead of using 24 PME ranks, the domain decomposition spans all 80 ranks, and no message about assigning PME ranks is printed.
Fix mdrun -nb auto -pme auto when GPUs are absent
The logic was flawed such that GPUs were "selected" for use even
though none had been detected. That led to the GPU behaviour of
avoiding using separate PME ranks.
Also made a minor fix to the logic for emulation. The new
interpretation of mdrun -gpu_id does not need to trigger an error when
GPU IDs have been supplied along with the emulation environmnet
#8 Updated by Mark Abraham about 2 years ago
- Status changed from Accepted to In Progress
Auto mode needs to respond to whether GPUs have been detected, and currently does not. I thought that was too hard to do (because compatibleGpus is local to the node, and the decision needs to be consistent across all ranks on all nodes), but hwinfo->ngpu_compatible_tot is useful for the purpose.