[torqueusers] random node selection using maui?

[Garrick Staples]

On Thu, Feb 08, 2007 at 02:29:13PM -0800, Peter Wyckoff alleged:
> 
> Hi Lennart,
> 
> the randomization goal is to have the computation on as many different 
> physical racks as possible.  This is for data locality (i.e., latency) 
> and IO bandwidth scaling for a distributed file system. 
> 
> The other way we are looking at is, just like you proposed, having a 
> node property called rackid-XXXX where XXXX = the subnet and then when 
> doing qsubs, requesting N/#racks of each rack type as a scheduling 
> preference.
> 
> I was thinking that if there were a way to be completely random (pseudo 
> random :)), we could get the same effect.

The 'ordered' scheduling in maui is largely based on the order in
pbs_server's nodes file.  You could just presort them there and then let
maui work as normal.

So the nodes file would basicly be something like this (assuming 3 racks
with 40 nodes per rack):

node001 rackid1
node041 rackid2
node081 rackid3
node002 rackid1
node042 rackid2
node082 rackid3
...