Storage QoS controls workloads that are assigned to policy groups by throttling and prioritizing client operations (SAN and NAS data requests) and system operations.
A policy group is comprised of one or more workloads and a performance limit that applies collectively to all workloads in the policy group. There are two types of policy groups:
You can view performance data for both types of policy groups. The names of system-defined policy groups start with an underscore.
A workload represents work that the cluster performs. There are two types of workloads:
I/O to storage objects that are not assigned to policy groups belongs to the "User-Default" workload.
You can view performance data for both types of workloads. The names of system-defined workloads start with an underscore.
The following illustration shows a user-defined policy group and a system-defined policy group. The user-defined policy group controls the user-defined workload, which represents the client operations from the application to the storage object. The system-defined policy group controls the system-defined workload, which represents the internal system operations that the cluster performs.