The read/write I/O ratio will determine how many disks are required to support the VDI workload in a RAID configuration. Now, we will learn how critical it is to understand the read and write I/O ratio to allow administrators to properly size storage arrays from a frontend (storage processors) and backend (disks) standpoint.

In the previous topic, we talked about the total number of IOPS that a virtual desktop produces during boot, login, and steady state utilization. IOPS may be read or written. Every time a disk block is read, we have a read I/O and every time a block is written, we have a write I/O.

The Windows operating systems are, by nature, very I/O-intensive, and most of those I/Os are write I/Os. This is actually a very interesting subject. During workload simulations, it is possible to identify that Windows is constantly issuing more write than read I/Os. However, the most interesting fact is that even when Windows is idle, it still produces more write than read...