As we discussed in our recent webinar, “What Better for VDI, All-Flash or Hybrid?” user acceptance is critical to a successful project. One of the keys to that acceptance is making sure that users are given at least the performance they are accustomed to from their physical desktop. A common mistake made when designing a VDI storage infrastructure is that the storage system is designed to meet the sustained performance demands of the users. While mathematically correct, this approach could mean failure of the project.
Virtual Desktops are Bursty
Designing for a sustained performance deliverable is fine when the workload is relatively consistent. For example, say the IOPS requirement for a virtualized server ranges from 200 to 250 IOPS at any given point in time. If you design for 225 IOPS you’ll meet the performance demand and probably not suffer any noticeable performance impact at peak. But what if the IOPS ranges from 0 to 100 IOPS, which is common for a virtual desktop? If you design for 50 IOPS and there is a peak demand for 100 IOPS, you’ll be 50% short and chances are the users will suffer a performance problem. In the VDI use case this can mean user frustration when logging in, starting an application or logging out.
Solving the Bursty VDI Problem
As we discuss in the webinar, hybrid and all-flash storage systems can both solve such problems created by wide ranging virtual desktop performance demands. But all-flash arrays fix it with a sledgehammer. The storage infrastructure is essentially designed to meet the peak performance demand, which unfortunately in VDI means that a lot of IOPS capacity goes wasted. Justifying an all-flash investment requires leveraging it for more than just the VDI architecture.
Hybrid arrays can also solve the bursty VDI problem, but require a little more planning and tuning. Virtual desktop images need to be locked into flash to meet this fluctuating workload demand but the rest of the VDI data set can count on a hybrid’s tiering mechanism to meet its performance needs.
When you register for our webinar, you’ll also have access to an exclusive Storage Switzerland White Paper “Cost Justifying Flash For VDI Storage”. In that paper we provide a guide to cost justifying the flash investment in a VDI infrastructure as well as how to determine which type of flash is right for you, hybrid or all-flash.