Read IOPs by Virtual Machine Disk This chart displays the top ten virtual machines with the highest number of read operations. Data is not displayed when the virtual machine is powered off. This chart is located in the Performance view of the datastore Performance tab. Table 129. Data Counters Chart Label Description Average read requests per second Number of disk read commands completed on each virtual machine disk, per second. Read rate = blocks read per second × block size ■ Counter: numberReadAveraged ■ Stats Type: Rate ■ Unit: Millisecond ■ Rollup Type: Average ■ Collection Level: 2