Service level metrics and definitions

The following terms and definitions are used within the NetApp Keystone:

  • GiB, TiB, and PiB. Measurements of data storage capacity using base of 1024 (1 GiB = 10243 bytes, 1 TiB = 10244 bytes, and 1PiB = 10245 bytes).

  • IOPS/TiB. The protocol operations per second requested by the application divided by the allocated logical size of the volume.

  • Availability is measured as a percentage of number of I/O requests successfully responded to by the service, divided by total number of I/O requests made of the service, measured at the service demarcation, in a given month, not including scheduled service downtime or unavailability of required facilities, network or other services to be provided by customer.

  • Durability is the percentage of data accessed without loss of fidelity, excluding customer-caused deletion or corruption.

  • Target IOPS per TiB. The guaranteed IOPS for all I/O requests made to a volume before the target IOPs per TiB threshold is reached. Performance on the volume is capped at the selected IOPS per TiB.

Note The target IOPS per TiB performance metric is calculated based on the logical consumed capacity in TiB.
  • Latency. Time to service an I/O request received from a client, measured at the service demarcation (storage controller I/O port).