[Mauiusers] Packing small jobs into node sets

[Ansgar Esztermann]

Hello,


on our clusters, the high-speed interconnect is partitioned into  
several differently-sized networks (at this point, we have a 24-node  
switch and a bunch of two-node "networks", i.e. two nodes connected  
back-to-back). I am using node sets to ensure that only nodes within a  
single network are allocated to multi-node jobs.

Now, I am wondering whether it is possible to make maui conserve  
resources like this:
a) prefer smaller networks to larger ones (i.e. use a 2-node "net" for  
a 2-node job rather than allocating two nodes out of a 24-node net);
b) when starting two 1-node jobs, pack them into the same 2-node net  
rather than occupy one node each out of two different node sets.

As to point b, this seems to work via backfill once the queue is full,  
but I'd like it on an empty cluster as well.


Thanks,

A.
-- 
Ansgar Esztermann
DV-Systemadministration
Max-Planck-Institut für biophysikalische Chemie, Abteilung 105