= Active IQ Unified Manager is a tool that enables you to define the performance and storage objectives for a workload using Performance Service Levels (PSLs). You can assign a PSL to a workload when initially creating the workload, or afterwards by editing the workload. The management and monitoring of storage resources are based on Service Level Objectives (SLOs), which are defined by service level agreements that are based on required performance and capacity. Active IQ Unified Manager provides a few predefined PSLs, such as Extreme Performance, Performance, and Value, and also allows you to create your own PSLs to meet your needs. You can also apply the PSLs to multiple clusters and workloads to ensure optimal performance and utilization of the underlying resources.Reference=Performance Service Levels,Managing Performance Service Levels