Desktop virtualization is an important strategy for organizations seeking to reduce the cost and complexity of managing an expanding variety of client desktops, laptops, and mobile handheld devices. Virtual Desktop Infrastructure (VDI) offers an opportunity to not only reduce the operational expenses for desktop management and provisioning but also to improve user mobility and data security.
A VDI deployment can place high performance and capacity demands on the storage platform. For example, consolidating large amounts of inexpensive stand-alone desktop storage into a centralized infrastructure can create tremendous capacity demands on centrally managed shared storage used in VDI deployments.
Performance demands are determined by the number of I/O operations per second (IOPS) generated by basic desktop client operations such as system boot, logon and logoff, and by desktop usage operations from different users. Storm events such as morning logons and afternoon logoffs by many users at approximately the same time can cause I/O spikes that place high performance demands on the storage infrastructure. Moreover, IOPS generated per desktop can vary greatly depending on the user type. For example, knowledge workers with several demanding applications can create significantly higher IOPS per desktop than task workers performing routine operations.
A cost-effective, appropriately-sized storage platform is critical for a VDI deployment success. The Dell Compellent SC8000 All Flash Array (SC8000 AFA) with its advanced storage architecture and feature set, combined with tight hypervisor integration, provides an automated, self-tuning storage system capable of efficiently scaling to satisfy VDI production-level workloads.
We have recently published a new VDI reference architecture document that demonstrates how 3,000 virtual desktops can be deployed in a Citrix XenDesktop environment leveraging a single SC8000 AFA comprising two controllers and one enclosure of 24 Solid State Drives (SSDs). The supported VDI workload was medium to heavy, with each desktop generating 30 IOPS at steady state. The SC8000 AFA delivered these IOPS requirements – 90,000 at steady state – with less than 3.5 ms of storage latency, indicating an excellent experience for the end-users.
The paper also provides details about the storage I/O characteristics under various other VDI workload scenarios like boot and login storms.