Take VMware's acquisition of application virtualization provider Thinstall as evidence that the virtual desktop infrastructure (VDI) model of server-based computing is still a work in progress.
Indeed, some IT professionals who are intrigued by VDI's security and manageability are turned off by its price tag and its high degree of resource utilization, whether that involves CPU, memory or storage. As a result, users are looking far and wide for alternatives.For example, consider Kalido, a U.K.-based developer of business intelligence software. About a year ago, the firm began outsourcing some of its research and development to a team of 10 developers in India and considered various methods of providing them desktop access. "We thought a lot about how to give those guys some resources," said Nick Gatt, Kalido's IT manager, with particular attention paid to cost.
The most obvious option was to provide developers with a physical desktop machine. But the PCs required to run Kalido's developer environment (full Oracle and MySQL databases, Visual Studio, WebSphere, JBoss, as well as the traditional suite of office applications) would have cost about $2,500 apiece and would have been extremely difficult to manage from the U.K.
Meanwhile, the licensing and infrastructure costs of Citrix Presentation Server (Citrix also has a VDI solution called Citrix XenDesktop) were deemed too expensive, and the VMware VDI approach consumed too many system resources – for CPU, memory and storage.SWsoft Virtuozzo's triad of advantages
Gatt's brainchild was to use an alternative form of virtualization -- SWsoft Virtuozzo -- which as soon as SWsoft completes its name change to Parallels, will be known as Parallels Containers. Gatt installed a baseline Windows Server 2003 operating system plus the necessary applications on top of an existing dual quad-core Dell PowerEdge server with 16 GB of RAM, and partitioned it into 10 virtual environments using Virtuozzo. To access virtual desktops, developers simply log in over IP to the machine using the Microsoft Remote Desktop Connection client that comes with Windows.
The result, Gatt said, has been performance that's "as fast if not faster than a dedicated desktop would have bought," as each developer sees up to 16 GB of RAM, depending on how many other virtual desktops are in use. The cost to Kalido was also substantially less ($14,000 versus $25,000 for standalone PCs), and "setup was quicker and backup is easier," Gatt said.In short, Virtuozzo "won on price, user experience and implementation," Gatt said. "You don't usually see all this at the same time."
In fact, Virtuozzo's virtual desktops have been so successful that the company will soon extend the concept to developers in the U.K. by giving them access to a pool of "ad hoc crash-and-burn machines" hosted on a similar Dell machine, Gatt said. And as the time comes to upgrade developers' local PCs, Gatt may also move them to a Virtuozzo virtual environment to simplify management. SWsoft's application templating approach, Gatt said, "makes building these machines almost instantaneous."Containers vs. VDI vs. Citrix
Using containers-style virtualization for virtual desktops is an increasingly popular, if novel, use for the technology, said Carla Safigan, director of GTM strategy and programs at Parallels. "About a year ago, customers started coming to us with this idea," she said, and now virtual desktops are the third most popular use case for Virtuozzo, behind consolidation and Web site hosting.
Like VMware VDI – but unlike Citrix Presentation Server -- using Virtuozzo for virtual desktops allows end users to customize their desktops. And because server editions of Windows all run standard desktop applications, there are no compatibility issues with these applications, Safigan said.Unlike VMware's style of VDI, Virtuozzo requires only one copy of an operating system to install, simplifying management and reducing the amount of storage consumed by each end user. Virtuozzo containers are also a good fit for end users with demanding performance requirements, Safigan said. "Our strong suit is our low overhead," she said. "We tend to do really heavy desktops that no one else can touch." There are downsides to this approach, however. They include a lesser level of isolation among environments than that among virtual machines, and – as far as Windows is concerned – the absence of a VMotion-style live migration, although Safigan said SWsoft is working on it. Virtual desktop buzzkill
But despite these characteristics, using Virtuozzo for virtual desktops is extremely rare, analysts said. And in truth, VMware-style VDI has yet to really take off. "There's a lot of interest in VDI, and a good number of pilots and [proof of concepts], but no one's really moved forward into production yet," said John Humphreys, a program vice president for enterprise virtualization software at Framingham, Mass.-based research firm IDC.
As it stands, VDI still suffers from several problems, Humphreys said. Graphics performance, for instance, is still far from adequate for users that need multimedia capabilities, and the cost of thin clients remains relatively high.But perhaps the biggest hurdle to VDI is licensing the Microsoft desktop, Humphreys said. "They make it incredibly difficult to do this legally," he said.
To be fair, last spring, Microsoft introduced Vista Enterprise Centralized Desktops (VECD), a new license model available to Software Assurance customers that permits instance-based rather than installation-based Vista desktops, enabling VDI. But according to Humphreys, since VECD is available only to Software Assurance customers – and because many shops aren't ready to take the Vista plunge -- most would-be VDI shops have no other choice but to purchase a retail version of Windows.But all hope for VDI is not lost, Humphreys said; far from it. Just as VMware bumped along for five or six years before becoming the powerhouse that it is today, "there's this bouncing around on the floor before you get to that inflection point," he said. "There's a lot of interest in VDI, it's just that it isn't happening as fast as everyone thought."
Let us know what you think about the story; email Alex Barrett, News Director.
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