In this blog post, I will explain why most VDI projects fail due to the 3 biggest storage problems with VDI and offer tools to solve them so you can avoid using the hashtag #VDIFail in your next angry tweet.
We love to hate VDI, but it doesn’t suck entirely
Yes, VDI is expensive, but companies with low complexity environments will save the most money. When desktop users have a limited set of applications, functionality and personalization, you can pool virtual desktops, rather than dedicating one to each user, and provision them on demand.
The average IT organization will balk at the (at least) 10 layers of a VDI infrastructure:
Problem #1: Storage is the Achilles heel of VDI
If 100 people tried to access the same piece of data on conventional PC infrastructure simultaneously, it would result in a denial of service. Storage for virtual desktops is exactly the Achilles Heel of VDI.
Josh Goldstein is VP of Marketing and Product Management at XtremIO. In his blog post titled Hidden VDI Planning Assumptions, he cautions against planning with reference architectures that are based around the limitations of the storage array, rather than the demand of persistent virtual desktops and their applications. He suggests that, to solve storage issues with virtual dekstops, make sure you plan using the average load on your own SATA drives in the desktop machines you currently use.
Goldstein also brings up a good point with hard-drive based arrays. When a desktop can only access the RAID group it happens to reside on, and that RAID group is being shared with other VDI users, you lose the ability to burst to high IOPS. You need a system that will scale with your needs while providing a high-performance experience for your users.
Problem #2: “My computer is too slow!”
To provide a persistent desktop that maintains personalized settings, shortcuts, files, programs and data is problematic. The more the user adds to their desktop, the more storage it takes up on the server.
Then, you have boot storm. Overwhelming the network with storage IOPS requests results in painfully slow boot-up times and an overall degradation of service – even if performance is good the rest of the time. VDI supports two demand sets. First, from users who demand control over their desktop personalization and applications. Second, from IT managing large herds of desktops. Utilizing flash storage arrays is how to get high IOPS, but more on that below in our EMC XtremIO flash storage example.
In an ideal world, IT would employ a Persistent Desktop VDI model to provide the customization the user wants, and the simplicity the IT team craves. Although it sounds ideal in theory, the Persistent Desktop model is very hard to deploy as it places extreme loads on storage performance and capacity.
Problem #3: The cost per desktop is way too high
The actual price of an individual personal desktop is dependent on the performance requirements of users. Reality check: it’s not going to be cheap. However, a virtual desktop can perform better than a physical machine at a reasonable price. VDI requires a Storage Area Network (SAN) and even the lowest-cost SAN will eclipse its desktop equivalent in price. The real cost of VDI storage is up to $1000 per desktop for storage. Really:
So, if you are planning a VDI deployment, you are aware it’s going to be complex, and that it isnt going to be cheap. you need to properly plan for a complex project that must (at least) consider storage performance, the user experience, IT management and cost.
VDI Planning isn’t as hard as you think
If a VDI deployment is something you need to figure out. You’re not alone.
There is no automated way to plan the requirements of a large installation of desktop virtual machines (silicon valley take note). According to VMware Labs’ Measuring True Virtual Desktop Experience At Scale you need to solve for 3 things:
- A typical office user workload
- An accurate measure of end-to-end latency
- A virtual appliance to configure and manage the workload run at scale
Once you have your requirements, you really want to test the whole thing in a lab or dev environment and perform the same operations that your VDI environment will do every day. I repeat, the only real way to test a VDI solution is to do the actual things the environment will do.
EMC XtremIO and the story of ITSAM– a Swedish IT provider
A lot of technical information is available about the specs, cost and performance of XtremIO in this blog post.
ITSAM supports six local governments in southeast Sweden. Their existing storage could not support their VDI deployment (also known as #VDIFail). It took twenty minutes to bring up one end user computing client! One of the staff members at ITSAM attended VMWorld and watched a full video demo of EMC’s XtremIO all-flash array. They chose XtremIO to maximize the performance of VMWare Horizon (with View). The result was over 300,000 IOPS and latencies of less than one millisecond.
The value of EMC and Softchoice
We love that XtremIO is priced in the middle of the pack, offers impressive performance and even a $1 Million dollar guarantee. Our EMC Storage Array Analyzer helps clients understand the current state of storage components and performance, identifies any problems, and provides recommendations for improvements to optimize the environment. Led by a Softchoice-certified consultant, we work with clients to provide guidance on best practices for configuring and managing storage arrays.
To learn more about the EMC Storage Array analyzer, or to consult a VDI expert, contact our team today or leave a comment below.