Virtual desktop reality

The requirements for fast, scalable and manageable virtual desktop infrastructure, according to Mike Jansen, DinamiQs’ VirtualStorm Lead Architect and Erik Westhovens, DinamiQs’ VirtualStorm Lead Developer.

“Unfortunately, all of these technologies have advantages as well as disadvantages and implementing these technologies means there will be trade-offs”
-Mike Jansen

The current buzz in the IT industry, apart from Cloud Computing, is definitely virtual desktop infrastructure (VDI). Less elusive than cloud, VDI has been building momentum in the past years, promising high performance, centralised desktops with full application stacks. To deliver on that promise it is key to understand the challenges and demands of large-scale centralised desktop environments. The list below addresses the main issues, but there are many more, smaller issues that need to be resolved in order to make any solution work.

The challenges of the traditional VDI (and for that matter fat client) solutions are many:

• Deploying of desktop images takes a lot of time
• Automating deployment is not trivial
• Managing images is like managing fat clients, nothing changes
• Traditional VDI total cost of ownership (TCO) is not compelling versus regular fat clients
• Storage for traditional VDI becomes huge, unmanageable and expensive
• Density of virtual machines on physical servers is constrained by memory, network and IO
• Updates and upgrades of applications causes downtime especially in large scale environments

In the industry today you will find many solutions that aim to improve any of the mentioned items. But unfortunately none address all of them. What you will find is that in many cases you trade off an advantage with a disadvantage. In fact, it seems that most solutions work around three SBC concepts: sharing, streaming and isolation. And most solutions will provide you with a hybrid solution that is neatly encapsulated in an 'intuitive' management environment. So far so good, but for any solution to actually scale, you need to ask yourself a couple of questions and see if and to what extent you meet a particular set of demands. Unfortunately, all of these technologies have advantages as well as disadvantages and implementing these technologies means there will be tradeoffs. But in order to effectively scale an environment and to make sure that the end-user experience is 'as-good-as' or better than a traditional fat client environment, no tradeoffs can be allowed. And this means that we have to create a system that is perfectly optimised to do just one thing and to do that extremely well.

The demands and requirements for true VDI are:

• Deploying desktops in (semi) real time
• One user per desktop with - if so required - full admin rights for that desktop
• Persistent, roaming profiles outside the OS image
• Simple automation and pre-provisioning of desktops
• Abstract applications from OS and OS from hardware
• Manage both image and applications inside the image
• Improve installation and de-installation of applications
• Reduce the storage requirements of desktops versus traditional VDI
• Reduce OS importance and focus on applications (ie make any Windows an application launch platform)
• Increase density of virtual desktops on servers through IO and memory optimisations
• Reduce management effort to the extreme (one admin for 10000 desktops, or better)
• Make it as 'green' as possible
• Make it as economically attractive as possible

Actually these were the demands from one of our customers for their intended VDI implementation. We found them to hold true for most if not all environments.

In many of the currently available products, the tradeoffs become visible when you ask yourself a simple question each time you look at a solution. That question is: "What about 10,000 users simultaneously?" All of a sudden you start finding bottlenecks if you apply those 10,000 users to the demands mentioned. If you share in his environment, you'll have many servers to manage, if you stream applications to (virtual) desktops you're running in severe IO problems both on the network and on the disk, but also in the number of provisioning servers required for specific and popular applications. Isolation is of course completely unmanageable for 10,000 individual clients.

To meet these demands DinamiQs developed the VirtualStorm concept: A highly optimised VDI environment that meets and exceeds today's standards.

The current state of the virtual world

So what is VirtualStorm really? It's actually a best of breed solution that is leveraged by a few pieces of code that glue all these solutions together to the concept that we call VirtualStorm. The components are VMware ESX, Microsoft Windows (yes, all Windows versions since 2000), Symantec Workspace Virtualization and the agents and applications that together form the DVS4VDI product suite. In effect, VirtualStorm is a highly scalable, well-behaved, low IO, high-density environment that virtualises desktops and applications to the extreme. And with everything that occurs, these questions have to be answered to full satisfaction: "Will this scale? Will a double workload within a short period of time work? How to keep it manageable? How to distribute workloads properly?"

There are currently many large customers who are setting up demos and proofs of concept and, considering the pace at which VirtualStorm is growing reseller and customer base, there are very busy times ahead.

About the future of true VDI

This article describes an optimal environment for large-scale VDI implementations in which both end-user experience, ease of support and scalability are maintained, to the extreme. This will result in certain paradigm shifts that require thought and perception to introduce in any given organisation. So keep the following in mind:

• Your desktop will become a screen. No more than that. A window on your actual desktop into the data centre. Best example of a simple screen device is Sun Microsystems' Sun Ray device. There will be others, no doubt.
• Your OS will become a launch platform for your applications. After all, what do you use an OS for, really?
• Density of desktops on physical server hardware will increase drastically. In general, VirtualStorm is not doing a lot with all the power at its disposal, so densities can increase as long as Moore's Law is in effect.
• Reduction of centralised storage for desktop OS and applications. Why provision many times when you only have to, once?
• Real time deployment of OS and applications.
• Strongly reduced data transport, resulting in instant availability of profiles and applications. Why use IO if you don't have to?
• For management it means one desktop to maintain, one central unlimited repository, scaling to millions, but managed by few. This is called the Power Of One

But really, this is not the future of VDI. This is what is available right now in VirtualStorm.

Erik Westhovens is an IT specialist with in depth knowledge of SBC environments and Windows infrastructures. He is one of the top application packagers in the world today and a frequent contributor to Symantec Connect. His experience and knowledge have allowed him to develop the components that are integral to VirtualStorm.

In the past 15 years Mike Jansen, who resides in Amsterdam, has designed and implemented large-scale infrastructures for various organisations. In recent times he has applied his knowledge to desktops and end-user experience in virtualised environments, resulting in a huge contribution to the invention and creation of VirtualStorm.