NetApp HCI Manual page 28

As an example, if block sizes are 4k, and bandwidth is 4000 KBps, the IOPS are 1000. If block sizes increase
to 8k, bandwidth increases to 5000 KBps, and IOPS decrease to 625. By taking block size into account, the
system ensures that lower priority workloads that use higher block sizes, such as backups and hypervisor
activities, do not take too much of the performance needed by higher priority traffic using smaller block sizes.
QoS policies
A QoS policy enables you to create and save a standardized quality of service setting that can be applied to
many volumes.
QoS policies are best for service environments, for example, with database, application, or infrastructure
servers that rarely reboot and need constant equal access to storage. Individual volume QoS is best for light
use VMs, such as virtual desktops or specialized kiosk-type VMs, that may be rebooted, powered on, or
powered off daily or several times a day.
QoS and QoS policies should not be used together. If you are using QoS policies, do not use custom QoS on a
volume. Custom QoS will override and adjust QoS policy values for volume QoS settings.

The selected cluster must be Element 10.0 or later to use QoS policies; otherwise, QoS
policy functions are not available.
Find more information
• NetApp Element Plug-in for vCenter Server
• NetApp HCI Resources page