By the numbers: Rackspace's UK cloud

The Slough-based datacentre is the cradle for the Rackspace's UK cloud and is currently being adapted to add further compute capacity and introduce free-air cooling to cut power use

Rackspace's datacentre in Slough has been built to balance efficiency with ease of access, as its managed hosting business requires it to offer a variety of services that include the rapid swapping out of servers.

It is also the cradle for Rackspace's UK-based cloud, and the company has plans to expand the facility by a further 17,000 square feet in August in a bid to boost its compute capacity. It also wants to make it more efficient by introducing some free-air cooling.

Rackspace datacentre

Rackspace keeps a vast amount of spare servers on site so that it can swap out hardware in case of failures. Photo credit: Rackspace

 Facility Two data halls within Rackspace's prime UK facility, with a third hall in the process of construction.
 Power usage effectiveness (PUE) 1.7. Once the expansion is complete, this should go down to 1.59
 Size Two halls of 36,000 square feet, plus an additional 17,000 square feet in August with the completion of the third data hall. 
 Racks 1,600, with a further 830 available in August
 KW per rack Average of 3.5KW
 CoolingDirect expansion via Crac units. Cooling coils if less than 14°C
 Hardware Predominantly Dell, with Cisco as the lead for networking. 
 Compute capacityn/a
 Designed by Hurley Palmer Flatt
 IT power3.3MW, with 1.1MW to be added in August, expandable up to 3.2MW
 Opened June 2008. Data Hall Three due to open in August 2011. 

See more of ZDNet UK's datacentre tour.