There are a few challenging technical areas that every VDI environment must overcome at some point. I have deployed VMware View 4 with great success and I’m looking forward to deploying VMware View 5 soon. Although the installation of VMware View components is very easy, there are some areas of design that need attention and may pose a challenge. The challenge level will depend on the environment and infrastructure you support.
Storage I/O: Storage is at the heart of server virtualization and it’s no different for VDI. When you centralize virtual desktops everything that occurs without VDI is compounded and can stress the storage infrastructure. I/O storms can occur from simple things like user login, boot up, and shutdown. For example, virus scan software, which could be configured to run on each virtual desktop, may use the same policy as physical desktops, and scans are commonly scheduled at the same time; scans are very I/O intensive. User experience will degrade quickly if the storage subsystem can’t handle peak I/O requirements. VMware recommends in their View 5 Performance and Best Practices white paper to use solid-state drives (SSD) for replicas and spinning media for the other virtual disks for best performance. Storage arrays that take advantage of SSD can support upwards of 80,000 IOPS if done correctly. If you’re using a network protocol for storage, jumbo frames, an isolated network and plenty of bandwidth to the storage array can make a difference.