Linux Ready to go Green, next is Windows vs. Linux comparison? interviews Linus Torvalds at, saying Linux is ready to go Green.

In an interview at the conference, the developer of the Linux kernel admitted that the operating system was lagging behind on power-management and energy-diagnosis tools.

"It is an area we were pretty weak in a few years ago and just building up the infrastructure took a long time, but now we are at a point where we have most of it done," Torvalds said.

"That doesn't mean we are done. Now we have an infrastructure in place... we have the tools to measure power and notice when the power is higher and why that is, which is pretty important. Before, it used to be a black box," he said.

This is just the start of putting power management in the OS, now they are going to have the work of making drivers power aware.  All it takes is one legacy driver to keep a system in a higher power state.

With Windows Server 2008 default power management turned on and shipping power management since Windows 2000, it will be interesting to see power comparisons between Windows and Linux in regards to performance per watt.

But, I think to do big power savings in a green data center you need a power management system which works across multiple systems.  The amount of power you'll be able to save on individual machines is best when you can turn them off.  Linux is playing catch up to Windows, but they could  change the game by providing the infrastructure to do power management across systems.