Day 2 of BriForum has enlightened me even further on why VDI has not penetrated the nearly as fast or deeply into end user environments. The appear to be two main causes that have either cause implementations to stall of fail in the marketplace and while both have technical aspects, one also political issues the consumer, the actual desktop user. IT Administrators view VDI as the answer to a number of issues with end user support.
IT views the use of gold images (linked/smart-clones) that are maintained by them (OS and application configurations and updates) as a way to provide a consistent experience for all users, as well has the helping to limit the number of helpdesk calls related to end user changes to their desktop. However, in a era where everyone is issued a desktop or laptop that has a company standard image to start with but allows the user to customize their environment with backgrounds, sounds, or icon that they use to show their individual personality or software that they are comfortable with to help complete their daily workload. In order to allow for end user customization there either has to be a layering of technologies in the VDI space to use the gold image or each user is provisioned a full VM that can be fully customized, which then brings the IT administrators back to almost where they started from when they started to explore VDI. This starting block is the OS and application updates and end user help desk calls due to user error or desktop hardware failure. These two views make it hard for IT to mandate VDI, since without user approval, no matter how effective the VDI solution is the project will be rejected or fail during the implementation phase. Since a hybrid model with single image VMs can be used for users of support applications or CRM style applications and engineering and test users could have full VMs or stay with the traditional desktops or laptops, this is not the sole reason the VDI has penetrated like server virtualization.
The second biggest reason is that desktop user I/O requirements are actually more intense then servers. In information presented in the sessions at BriForum studies have showed that the average of server I/O is 2.5 IOPs versus the average of a desktop user being 8-16 IOPs. A large part of this because server applications and operating systems are designed specifically to be very efficient because they are servicing a broader audience with the services that they provide. Desktop applications and operating systems are not as carefully architected as the hardware is servicing a single user with the a standard workload of email, document reading/authoring, web browsing, streaming music or watching videos. As result of this difference in I/O requirements, it is not as simple as taking the original architecture of a server virtualization project and using that same architecture to the VDI project.
VDI projects need to be architected from the ground up with new requirements for storage (both physical disk and the layout of the shared storage), networking, and end user needs and wants. As a power user myself that has large amount of time and pride in getting my laptop setup with all the tweaks, applications, and personality that make using it everyday go smoothly and take the mundane out of the work day.
Being a huge advocate for the merits of VDI, even to point I am exploring ways to implement it at home for my family to help eliminate the need for refreshing and managing so many different types of hardware, I am going be more diligent when proposing or helping my peers with VDI implementations.
Nice write up Chad! I’ll admit that I’ve harbored a little doubt around the take-off of VDI and at times I’ve been shy to the VDI complex. I’ve got no doubt that at some point VDI will latch on in amazing ways as it finds its home as a solution to some limiting situations like budget, power, manageability, future-proofing and portability. Essentially finding efficiency by doing what so many are trying to do… more with less.
I too still believe that a moderate percentage of human users, myself included, are coupled to their physical desktop as an extension of their personality or profile and as such picks away at the success of VDI solutions using core images with differencing disks for each VDI. I mean we really don’t want to do something that may impact end-user productivity. Based upon what I’ve read and what you’ve written I see this as breaking down into 2 high level segments of desktop organizations… those that will likely enforce company desktop usage to a virtual instance connected-to by way of aging physical gear (something that is currently successful today) || or organizations that retain desktops virtually, but allow users to hold their profile and allow personal customizations (I wonder how much roaming profiles can accommodate these users). I also thing application virtualization can play a huge role in how successful both types of VDI play out.
I especially liked the point you discussed around the variance in typical server performance versus desktop performance. Servers are, in a lot of cases, architected to be similar to each other in terms of versioning, sizing and most importantly… predictability. Making VDI more predictable, in my opinion, allows us to architect solutions with greater ease and reliability. Thanks for the posts!
hey, nice blog…really like it and added to bookmarks. keep up with good work