There’s a lot of interest in new converged hardware platforms for VDI. Converged platforms present a scalable architecture where you grow capacity by adding devices that provide both compute and storage capabilities. This would be in comparison to more traditional architectures. People used to just buy servers with disk in them. These were fine as far as they went, but over time, it was a hassle to manage each individual box. Along came storage area networks and servers were relegated to providing the compute needs for your data center. Now with converged devices, the boxes automagically create pools of compute and storage as new ones are added. No expensive SAN, no granular management, just goodness. That’s the theory anyway.
Converged architectures look to solve a number of problems for VDI:
- Storage price per user. Converged architectures should be cheaper than traditional SAN architectures.
- Linear Cost Scalability. Each box adds to the capacity of the farm linearly. With traditional SAN approaches, the solution cost scales in fits and starts. At certain break points, the solutions will require new chassis, controllers, or other larger purchases. User 2001 may cost significantly more than user 1999 if he requires a whole new EMC VMAX.
- IT Politics. Many VDI engineers are forced to build their solutions based on current offerings from the storage or compute teams. These solutions are often not great price/performance fits for VDI. If the storage offerings have been built primarily to meet the needs of large structured data requirements (Oracle, for instance) they’re not going to serve VDI well. A converged solution can allow a VDI architect to break free from these political silos and buy a purpose-built VDI appliance.
From an architecture standpoint, I think a VDI architect has two primary missions.
First, get performance right. Performance needs to be predictably adequate. Performance is something you cannot just average over time. Just ask my wife. If you’re a good husband most of the time but a crappy one on occasion, the occasions will rule the day. Beyond that, it’s all about driving down the cost per user. The costs should be all-inclusive. Hardware, software, and personnel costs should all be considered.
So, is the performance of converged systems adequate? Sure, they can be if you build them right. What about cost per user? This is something you have to build and measure for yourself. Many solutions are, some are not.
I feel like I need to say a few harsh words about complexity. Complexity is the devil. Complexity will drive your costs up and your performance down. Complexity is a factory that builds outages and pollutes the air with finger-pointing. When comparing traditional and converged solutions look carefully for areas of complexity and stamp it out like the roach that it is. Complexity is not your friend.
So, is a converged solution right for you? Could be. Just follow these steps:
- Get your cost model down.
- Pilot to compare cost and performance.
- Shun complexity; embrace simplicity.
Walk the path of convergence young VDI Jedi and perform at low cost you will.