In an attempt to gauge prices, users tend to calculate their own numbers or equations to figure out the average number of IOPS. But, Madden asked, does "average" refer to a 24-hour period or an eight-hour work day? And since you can't designate more IOPS for busier times of day, you need to be prepared to support the maximum number of IOPS at all times. The scattered and divided nature of a VDI environment means customers often don't know how many IOPS individual users will need.
An assessment tool is one way to understand how many IOPS users need. A product like Liquidware Labs' Stratusphere FIT would allow you to collect data for a month or two to get a handle on your user's VDI requirements. However, since this is an additional cost, some customers are reluctant to shell out the cash for a pre-VDI assessment. And just like delaying routine health care can lead to costly treatments down the road, Madden explained, not knowing your VDI requirements from the get-go can result in added costs for an underperforming environment in the future.
"The reality is that since a user's 'pre-VDI environment' is based on hundreds of individual computers, with hundreds of individual hard drives scattered all over the place, customers just flat out don't know how many IOPS their VDI users will need," he said.