[Beowulf] Green Cluster?

[Perry E. Metzger]

fkruggel at uci.edu writes:
> I am wondering whether there is any mechanism to automatically
> power down nodes (e.g., ACPI S3) when idle for some time, and
> automatically wake up when requested (e.g., by WOL, some cluster
> scheduler, ssh). I imagine that I could cut down power & cooling
> on our system by more than 50%. Any hints?

Depending on the motherboard, there are ways to do this. You can do
wake on network and other tricks. However, if you would really save
half the power, that implies that your cluster is half idle. If it is
really half idle, why aren't you simply shutting half of it down?

Perry