That would be very kind of you and most welcome!
> On Nov 14, 2020, at 12:38 PM, Alexei Colin <aco...@isi.edu> wrote:
>
> On Sat, Nov 14, 2020 at 08:07:47PM +0000, Ralph Castain via users wrote:
>> IIRC, the correct syntax is:
>>
>> prun -host +e ...
>>
>> This tells PRRTE that you want empty nodes for this application. You can
>> even specify how many empty nodes you want:
>>
>> prun -host +e:2 ...
>>
>> I haven't tested that in a bit, so please let us know if it works or not so
>> we can fix it if necessary.
>
> Works! Thank you.
>
> $ prun --map-by ppr:64:node --host +e -n 1 ./mpitest &
> $ prun --map-by ppr:64:node --host +e -n 1 ./mpitest &
>
> MPI World size = 1 processes
> Hello World from rank 0 running on nid03835 (hostname nid03835)!
>
> MPI World size = 1 processes
> Hello World from rank 0 running on nid03834 (hostname nid03834)!
>
> Should I PR a patch to prun manpage to change this:
>
> -H, -host, --host <host1,host2,...,hostN>
> List of hosts on which to invoke processes.
>
> to something like this?:
>
> -H, -host, --host <host1,host2,...,hostN>
> List of hosts on which to invoke processes. Pass
> +e to allocate only onto empty nodes (i.e. none of
> whose cores have been allocated to other prun jobs) or
> +e:N to allocate to nodes at least N of which are empty.
