Following up on yesterday's blog about green storage, there is another key area in the data center that is ripe for a makeover: networking.
In fact, without an upgrade to virtual I/O technology, that vast majority of both the energy and performance gains of server virtualization will probably never be realized.
I've blogged at length in the past about the fact that having umpteen virtual machines in a single server is an exercise in futility if they all have to vie for a single I/O port out the back of the box. This is the classic "bottleneck" you've been hearing about over the past decade or so.
But now that more and more enterprises are getting past the experimental stage of virtualization, where two or three machines per box was sufficient, the concept is quickly moving off the drawing board and onto the data center floor. The beauty of I/O virtualization is that it allows you to consolidate more machines on a single server and replace much of the networking hardware you've grown accustomed to -- a double-whammy in terms of energy efficiency.
Neterion took a major step forward in virtual I/O technology this week at the Intel Developers Forum. Along with Red Hat, the company showed the first implementation of the Intel's Virtualization Technology for Directed I/O (Intel VT-d), which employs what is called single-root I/O virtualization (SR-IOV) that allows even I/O-intensive applications to take advantage of virtual environments. Neterion says its X3100 10 GbE adapter is capable of providing 10 GbE-equivalent line rates across multiple applications.
Also eager to make its mark in virtual 10 GbE networking is VirtenSys, which just came out with the VirtenSys I/O 4000 Series switch that can be deployed in unified environments with mixed networking and storage traffic. The device can handle Ethernet, SAS/SATA, Fibre Channel and Fibre Channel over Ethernet, which goes a long way toward reducing the number of network interface cards and host bus adapters that are currently eating up energy in non- or low-virtual environments.
Of course, there are green networking solutions of the non-virtual type as well. Adaptec, for example, recently unveiled the hybrid Max IQ storage controller, which provides intelligent routing to divert frequently accessed data to an SSD tier. With a line rate of 1.2 Gbps, the device cuts down on hard disk usage in favor of the more energy-efficient SSD, while producing a fivefold increase in critical data throughput.
The raw technology in the latest networking gear is impressive, but to gain the most band for the buck you'll need to investigate some of the latest data management software, according to Margalla Communications' Saqib Jang. Tools like VMware's NetQueue manages multiple receive queues, while Citrix XenServer has the added benefit of allowing NICs to access guest memory directly, offloading much of the network processing from the CPU.
Whether your goal is greater energy efficiency, increased performance or both, networking is what really brings it all together. Virtual environments acting in isolation will only get you so far. It's the ability to transfer data from place to place that makes all the difference.