VDI deployments depend heavily on the intelligent usage of storage and on high-capability storage systems. The typical VDI project begins with a pilot program using existing physical servers and existing storage systems. The next phase usually involves scaling the VDI deployment to a threshold of close to 30% of the desktops. It is during this phase where the storage issues become apparent. The success of the VDI project will hinge on acquiring the right high-capability storage system – usually as an emergency purchase. The final phase is to scale to more virtualized desktops if the emergency found in the 30% phase can be dealt with satisfactorily.

The features most important with the high-capability storage systems include:
• Intelligent caching and data placement,
• Tiering of data – usually with solid state devices,
• Thin provisioning,
• Wide striping, and
• Cascadable read/write snapshots

Evaluator Group provides a document that discusses the needs for a storage system with VDI.

Our advice to IT includes a method for avoiding the emergency purchase by proactively understanding whether a storage system will meet requirements for a VDI project. The most effective way is to use a benchmark for VDI that focuses specifically on storage issues, and can show the right configuration to support the number of virtual desktops in use and the response time required.

The IT team needs to understand the type of workloads on virtual desktops required from specific users — such as a knowledge worker (using office tools), developer or financial analyst — and have the ability to dial in the right type of workload into the VDI benchmark. Acquiring a storage system with the correct amount of I/O streams requires a benchmark that will give IT enough information and confidence during the planning for a VDI project to make an informed selection.

Stay tuned for more information from Evaluator Group on storage benchmarks for VDI environments.

(Randy Kerns is Senior Strategist at Evaluator Group, an IT analyst firm).