[torqueusers] reducing energy usage of torque

[Arka Aloke Bhattacharya]

Hi everyone,

I am a PhD student at UC Berkeley, and I wanted to add a "turning off
idle/underutilized servers" feature to our 100 server torque+maui
deployment. However, I want to implement this feature using only existing
torque+ maui interfaces and extensions ( i,e *without modifying* the torque
or maui source code in any way ).

My proposed way is to
1. monitor the maui queue length , and estimate the number of servers I can
switch off.
2. I would then use "pbsnodes -o <nodename>" command to render a certain
number of servers offline for scheduling.
3. A bash script would turn the servers off.

The servers would be turned back on (and added to the torque nodes list)
when the queue length increases beyond a certain threshold.

I had two questions :

1. Is there any existing open source code which already implements the
"turning off idle servers" functionality in torque ?
2. Are there complications that would arise if I implemented the
"turning-off idle servers" feature in my proposed way ? [ e.g - Is it
possible that after turning off servers, they would lose some state and
hence would not get added to the torque <nodes_list> when turned back on?
Are there long lived TCP connections which need to be restarted separately
? , etc ]

It would be great if anyone could help.

Thanks a lot,
Arka.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.supercluster.org/pipermail/torqueusers/attachments/20120226/a9463fcc/attachment.html