One of the big challenges of a VDI deployment is ensuring that the storage used to host the virtual machines not only has the capacity necessary for your deployment, but also the performance users need. One of the never-ending challenges for those building storage is balancing volume, cost and speed. It’s a version of that old joke about “Fast, good, cheap: You can only pick two." In this case the joke is: “Performance, capacity, speed: You can only pick two.”
While it’s possible to get very large hard drives at a relatively low cost, the hard drives don’t perform well. Very large solid state disks, the type that would be wonderful for hosting the virtual machines used in a VDI workload, are extraordinarily expensive. Given that VDI is usually implemented as a way to save money, forking over a ton of cash for solid state storage to ensure the best possible performance reduces the likelihood that VDI will an economical solution.
Luckily, there is a way to deliver high performance without incurring the high cost of completely solid state storage. Tiered storage allows you to create an array that combines both high performance solid state disks with cheaper and slower traditional hard disk drives.
An interesting fact about storage is that approximately 20% of data stored in a disk gets 80% of the read and write operations, with this figure fluctuating based on workload. Using a disk array configured for tiered storage, the storage driver is clever enough to move the data that is frequently accessed to the “fast” solid state storage while moving the data that is accessed less frequently to the slower-spinning magnetic hard disk drives. You won’t get the performance of an array that’s comprised completely of solid state disks, but you’ll get performance that’s pretty close, at a fraction of the cost.
Tiered storage allows IT organizations to give users high performance VDI for applications and data that matter most, without breaking the bank.
Underwritten by HPE, NVIDIA and VMware