In some cases, when analyzing the storage needs for a VDI platform we look at saving disk space when using template-based or non-persistent desktops. Nevertheless, it is necessary to bear in mind that all the I/O operations on disc in a standard job platform are made on local discs located in each post.
In a VDI environment, all these I/O operations take place concurrently on shared storage. Tasks such as updates of OS patches, antivirus, user logins scans... produce a large amount of concurrent I/O operations that are referred to as "storms". These storms produce a deterioration in the performance of the storage because these I/O operations are accumulated in queues and this, obviously, causes an irregular performance of the virtual desktops.
Therefore, it is essential to know what are the necessary IOPS so that our VDI operates with full guarantees, using technologies such as SSDs, disks tiering, etc.