[maker-devel] Hyperthreading

[System Admin]

We are using maker in a cluster with mpich.  Currently hyperthreading is 
on and we use 'mpiexec -n <cores>' to start maker.  Our machinelist file 
for mpich specifies the total emulated cores for each node.
With hyperthreading on, we have up to 256 total emulated cores available.

Which is the optimal scenario?
1. Use '-n 256'
2. Use '-n 128' with hyperthreading still on
3. Use '-n 128' with hyperthreading turned off

Thanks