In-Depth

Product Roundup: It's Virtually Easy Being Green

A roundup of green alternatives in the virtualization space.

• By Keith Ward
• April 01, 2009

Perhaps the greenest of virtualization technologies is server consolidation. Putting more servers on fewer physical boxes has a domino effect on lowering resource consumption: Fewer servers mean less power consumption; lower power usage and fewer servers mean less heat is generated in the data center; less heat in the data center means less cooling needed to keep the servers humming, which in turn means even less power used. It's a green feedback loop.

The same can be said of virtual desktop infrastructure, also known as desktop virtualization or VDI. VDI consolidates desktops in the data center, which are then accessed remotely by end users. That means desktops can use thin- or zero-client devices, which consume a fraction of the power of a traditional desktop or laptop. This can result in large power reductions. Witness an IT administrator at the University of Maryland who instituted a VDI solution and says that his small, silver Pano Logic boxes consume about five watts of power each, compared to 150 watts in a traditional thick client.

However, these resource savings don't happen without a management framework that orchestrates the environment. What follows is a rundown of the major virtualization vendors that offer a green alternative to traditional computing. Note that these listings are in no particular order.

CiRBA
CiRBA Inc. is unusual in the industry in that it doesn't try to manage your infrastructure; instead, its Capacity Management Analytics examines your environment and recommends the most power-efficient way to consolidate. It also can tell you the impact on power consumption before making a change to your data center.
CiRBA works on both physical and virtual systems. After the analysis, it displays the "CiRBA Cube"-a visual representation of whatever you're modeling. There are more than 60 parameters that can be set.

Microsoft
Microsoft has been spending a lot of time and money developing System Center Virtual Machine Manager (VMM), which has a number of technologies for going green. One thing to remember, however, is that the full green benefits of VMM are only available with System Center Operations Manager (SCOM) 2007, meaning you'll need to buy the full System Center, not just VMM.

For instance, Performance and Resource Optimization (PRO) is a VMM feature you only get with SCOM 2007, because it leverages SCOM's deep monitoring capabilities to do its job. Separate from SCOM, VMM also offers Intelligent Placement, which finds the best match between virtual machines (VMs) and physical servers to optimize efficiency.

VMware
The granddaddy of all virtual managers is VMware Infrastructure (VI), which includes a number of green technologies. VI 3.5, the latest version, includes the Distributed Resource Scheduler (DRS); DRS in turn has a new feature called Distributed Power Management (DPM), which watches power usage across the data center and shuts down unnecessary physical servers, potentially saving a lot of resources.

VMware Inc. also has a VDI solution called VMware View. View uses thin clients, along with dynamic workload balancing and distributed power management, to reduce power consumption. On its Web site, the company claims that Huntsville Hospital in Alabama lowered its energy consumption by 72 percent using VMware View. Although those numbers may seem like marketing hyperbole, they fall in line with the results others have reported about VDI.

Citrix
Citrix Systems Inc. got into the VDI game in August 2007 when it bought open source hypervisor vendor XenSource. It has since built on the Xen base to develop XenServer, which provides server consolidation, and XenDesktop, a well-regarded desktop-virtualization solution.

In February, Citrix did something highly unusual when it released a full version of XenServer for free. Citrix hopes this move-which gives many of the green benefits of virtualization away for no cost-gets XenServer into more enterprise settings. It will be worth watching how VMware responds to Citrix's aggressive move.

IBM
IBM Corp. is one of the few companies that offers green technology on both the software and hardware end of things. On the hardware side, it has the new POWER6 platform architecture, which it says is much more power-efficient than previous iterations.

POWER6 systems include EnergyScale technologies. EnergyScale includes power trend-reporting information; static and dynamic power-saving modes; power capping, which enforces power limits; and more.
Managing all of this is Systems Director, currently at version 6.1. Much of the energy efficiency is brought about by Active Energy Manager, which is now baked into Systems Director. All this integration means that you can go green end-to-end with IBM.

Virtual Iron
Virtual Iron Software Inc. is a virtualization vendor that primarily targets the small- and midsize-business space with lower-cost options. The latest version, 4.4, contains an experimental feature called "LivePower" that allows organizations to power off underutilized physical servers, saving on power and cooling. Before it does that, of course, it migrates running VMs to production servers that aren't being powered off.

Although LivePower is still in the test stage, Virtual Iron says it's been deployed at "key" customer sites. Virtual Iron estimates that companies could see at least a 25 percent reduction in power and cooling costs.

Configuresoft
Configuresoft Inc. is a virtualization-management company. Its Enterprise Configuration Manager (ECM) has a number of green features. Among them is a power-management toolkit to monitor power usage among servers and end-user devices like desktops and laptops, and enforce policies on that usage. ECM also provides advice on which servers are the best candidates for virtualization, in order to make best use of resources.

Additionally, ECM has an unusual "cold standby" feature for backup and disaster recovery. This lets admins prioritize backup and standby servers, turning off those that house less mission-critical apps.

PlateSpin
One of the oldest companies in the young virtualization space is PlateSpin, which was recently bought by Novell. Its main green product is Recon, which helps in designing the most efficient virtual environment.

A number of products in this space do some of the things Recon does, but often don't go into the depth of detail. For instance, Recon's Capacity Planning Module analyzes five different factors that affect efficiency and performance, including CPU, disk, memory, network and time. That's more than most solutions. You can also do power and cooling analyses for different "What If" consolidation scenarios. Recon also offers detailed scenario modeling and planning.

Parallels
The virtualization solution that provides the best density-and therefore the most efficient operation-is OS virtualization, in which a single OS is cloned and instances of that OS are kept in isolated containers. It's complicated technology, but hosting providers, which are the main users of OS virtualization, find that they can put many more VMs-containers, in this usage-on a physical server than standard server virtualization.

The leader in this is Parallels Inc., formerly known as SWsoft. Parallel's OS virtualization is known as Virtuozzo, and has been around for years. Parallels has also developed a more traditional server-virtualization product, Parallels Server, which is currently in beta. And for those who use Apple Xserve servers, Parallels offers the only server-consolidation platform for products from Apple Inc., called Parallels Server for Mac.

Cassatt
Cassatt Corp. is a vendor with a narrow focus on power management and green technology. Its flagship product, Active Response, has four different editions that offer increasing levels of power management and functionality. Policies for managing power are based on four categories:

• Demand-based
• Event-based
• Capacity-based
• Time-based

One attractive aspect of Cassatt's technologies is that they don't require any modification to existing hardware or software, instead relying on power technology already built into most modern servers.

Intel and AMD
It's worth noting that the two big chip makers, Intel Corp. and AMD Inc., are also working to make their processors more green. Intel's virtualization-enabled chips fall under the moniker Intel-VT, while AMD's go by the brand name of AMD-V. Currently, AMD ships a larger percentage of chips with embedded virtualization technologies than does Intel.
However, both companies are working hard to ensure that power usage is carefully managed; this is a special concern as the number of cores on a chip increases, which leads to more heat and greater need for power and cooling. For instance, one new technology being developed by AMD turns off power to some of a chip's cores if they're not being used.
Not to be outdone, Intel is touting its new hafnium-based circuitry and 45nm technology, which the company says will boost processor energy efficiency, leading to lower power and cooling costs.

Growing Green Options
Even from this brief overview, it's obvious that virtualization vendors are leading the charge toward a greener environment. It's also worth nothing that we're at the beginning of the virtualization revolution: As the technology matures, more efficiencies will undoubtedly be gained, and server consolidation will improve as density-the number of VMs that can be run on a physical server-increases, leading to even more resource reduction. Given that the more companies virtualize, the more money they save, it's a safe bet that virtualization is likely to grow at a pace unmatched by any other sector of the IT industry.