The Disk chart displays historical statistics on disk usage for the selected local volume.
The following table provides information on predefined views and counters.
Datastore Usage (Bytes)
Disk/Physical Disk: Disk Read Bytes/sec
Rate at which bytes are transferred from the disk during read operations.
Disk/Physical Disk: Disk Write Bytes/sec
Rate at which bytes are transferred from the disk during write operations.
Disk/Physical Disk: Disk Bytes/sec
Rate at which bytes are transferred and is the primary measure of disk throughput. To analyze transfer data based on reads and writes, use Disk Read Bytes/sec and Disk Write bytes/sec, respectively.
Datastore Queue Length
Disk/Physical Disk: Avg. Disk Queue Length
Average number of both read and write requests that were queued for the selected disk during the sample interval.
Disk/Physical Disk: Disk Transfers/sec
Number of reads and writes completed per second, regardless of how much data they involve. Measures disk utilization. If the value exceeds 50 (per physical disk in the case of a striped volume), then a bottleneck might be developing. To analyze transfer data based on reads and writes, use Disc Read/sec and Disk Write/sec, respectively.
Disk/Physical Disk: Avg Disk sec/Read
Average time a read from the disk takes.
Disk/Physical Disk: Avg Disk sec/Write
Average time a write to the disk takes.