Power Down

It's no secret that data centers are power gluttons.

Its no secret that data centers are power gluttons. With power densities of 100 watts per square foot or more, electricity usage of a single data center can far exceed that of a comparably sized office building. But InfiniBand may provide data centers with dramatic reductions in energy needs.

The new standard does away with the peripheral component interconnect bus, known as the PCI bus, which will allow server makers to do away with PCI cards.

"A PCI card consumes 30 watts of power," said Philip Brace, director of product marketing at Intel. "There are significant reductions in electricity consumption that will be gained through the elimination of PCI cards." The potential savings are easily calculated. If a data center can eliminate PCI cards in 200 servers, it will reduce its power consumption by about 6,000 watts — enough to power six average homes.

In InfiniBand-capable servers, the work formerly done by the PCI card — managing the input and output of information — will be done outside of the server by switches on the InfiniBand network. And that network can handle dozens or even hundreds of servers or server-like devices.

InfiniBand may also allow further gains. Because data flow to and from the server will be managed by the InfiniBand network, data center operators may be able to do away with many of the network interface cards, Ethernet and Fibre Channel cards that are often used inside individual servers.

"Eventually under InfiniBand, youll only have one cable coming out of the server, and it will be used by InfiniBand for clustering, communications and storage," explained Eyal Waldman, CEO of Mellanox Technologies, an InfiniBand semiconductor start-up.

Mellanox predicted a standard server would use about one-third more power than an InfiniBand-capable server. The company estimated that a standard server equipped with all of the needed switching and I/O cards consumes 254 watts of power, and that a comparable InfiniBand server will use 190 watts. The company believes InfiniBand equipment will cost less, take up one-third less space in the data center and perform better than standard equipment.