Don’t Discount the Network in the Push for Energy Efficiency
In terms of energy consumption, network infrastructure hardly compares to servers and storage. It can still make a difference, though. Now that much of the low-hanging fruit in datacenter efficiency has been identified, if not picked already, the time has come to pay attention to some of the less obvious means of achieving green IT.
As in the server world, the most obvious place to look for efficiency opportunities in the network is on the processor. The same technologies that help streamline application and data processing also work on the network side. More networking solutions now use the ARM architecture, for example, such as Brooadcom’s recent StrataGXSoC for the network control plane. The BCM58525 Series features dual-core Cortex-A9 processors that clock in at 1.2 GHz and should cut power consumption down to less than 1 watt per core, even as performance increases some 20 percent over existing StrataGX solutions. Broadcom aims the device at enterprise edge networks, where it can take on such applications as collaboration, video conferencing, and surveillance.
Intel's pursuing a low-power networking solution as well. The company is gearing up for the release of the new Rangeley version of the Atom SoC. Supposedly, the device, built on the 22 nm Silvermont architecture, runs twice as fast as the new StrataGX, 2.4 GHz, but keeps power down to about 8 watts for an eight-core design. Intel claims a 35 percent performance bump versus the 32 nm Saltwell family and has thrown in its VT-x virtual hardware assist platform and an SSE instruction set for improved digital signal processing.
Higher up the stack, a number of recent developments promise to streamline network architecture by reducing hardware footprints. OCZ Technology and Mellanox, for example, recently teamed up on a new flash I/O and fault tolerance (FT) solution for clustered VMware environments. The package unites the Mellanox ConnectX-3 EN 40 GbE NIC with OCZ’s VXL replication software to enable VMware datastores in SAN-less clusters. This doesn't just provide for high-efficiency cache and flash volume distribution over the PCIe bus. It also reduces the number of Ethernet connections to the server by channeling more data through a single 40 GbE pipe.
But this may only be the start of what is possible on the interconnect. According to Research and Markets, the need for both energy efficiency and the flexibility to deal with Big Data and other loads will spur increasing demand for optical interconnects over the next four years or so. With datacenters consolidating to the point that they will be tasked with massive parallel operations, copper infrastructure looks likely to prove too slow and expensive to maintain over the long term. For these reasons, the firm expects the rack- and board-based OI market to double by 2018 to $2.2 billion.
In the grand scheme of things, power efficiency gains in the network will only marginally impact overall enterprise energy consumption. But with networking infrastructure under pressure to become more flexible and scalable, it’s reassuring to know that both goals can be met while keeping the lid on the network power envelope.
Despite the enormous progress brought by virtualization and other technologies over the past decade, IT remains perceived as one of the top energy consumers in the world, with overall consumption set to increase over the next few years due to increased data loads. So even if GB/watt improvements going forward are incremental, the industry can take at least credit in the fact that the ball is still moving in the right direction.