Power-Aware Dynamic Reconfiguration of Server Pools in Virtualized Cloud Environments

In our prior blog entry we saw that a common technique to reduce lighting power costs in residential and commercial buildings is to turn lights off in unused rooms.  This concept is so widely accepted that we rarely give it a second thought, let alone challenge it.   If that’s the case, why has this concept not been applied to servers in a data center, blazing away, drawing electricity 24 by 7, 365 days a year even at times when there is no work to be done?  There are more extreme cases of “dead servers walking”, servers that are no longer associated with useful applications, but have not been unplugged.