We've had PC turn-off, now for server turn-off

Everyone knows that you should turn off your PC when you leave the office to help cut carbon emissions, but what about the energy-hungry servers that are locked away in your datacentre? Can you turn those off when you're not using them?

Conventional wisdom in the IT industry states that you should never turn off a server, just in case it fails to come back on again when you need it. But one UK software company is now exploring whether it may be possible to automatically turn off underused servers, slashing energy use and carbon emissions in the process.

1E made its name with its NightWatchman PC power management system, which allows companies to automatically turn off PCs that would have been left on overnight without losing any of the users' work.

The company is now attempting to apply this approach to the world's datacentres and yesterday launched the second version of its NightWatchman Server Edition, moving it a step closer towards the goal of being able to turn off servers that are not in use.

"We are a little way from getting to the point where you can turn off a server and reliably turn it back on, but there's no doubt we will get there," 1E product manager Andy Hawkins told BusinessGreen.com. "The technology to do it arguably exists today, it's just that no one has joined it together."

1E argues that the emergence of so-called virtualisation software, which allows firms to run online applications on "virtual machines" that can be transferred between different servers, means it is technically feasible to automatically shift applications from one server to the other, freeing up unused servers that can then be turned off.

Hawkins said the latest version of the company's software marks a stepping stone towards this point, providing firms with the ability to track how much energy is used by each virtual machine and identify servers where the amount of energy being used can be reduced.

"Modern servers have power management systems but IT managers are either unaware of them or reluctant to turn them on," he explained. "Our software analyses whether a server is doing useful work and can then activate the power management system and throttle back the CPU or fan speed where it is not needed to do useful work."

The company estimates that simply using power management systems can cut server energy use by an average of 12 per cent, with further savings realised by commensurate cuts in the energy needed to cool the datacentre.

Hawkins admits it will be a challenge to convince IT managers that they can safely power down, or in a few years turn off, under-used servers. But he remains confident that firms can deliver deep cuts in the energy and carbon footprint of their datacentres, simply by understanding which servers are undertaking useful work.

"There is a mindset where people are reluctant to apply power management in the datacentre," he said. "We need to make people aware that this technology has been around for a little while and that the benefits are significant."