Clustering ESXi hosts for compute aggregation and power management
When you form an ESXi cluster, the compute resources, namely, the CPU and memory resources, can be managed as an aggregated pool of resources and load balanced. This is achieved by enabling vCenter's distributed resource scheduler or DRS. DRS is also used by other solutions like vSphere HA, vSphere Fault Tolerance, vCenter Update Manager, and so on. We will learn more about how these solutions leverage DRS later in this section.
Clustering of ESXi hosts also enables the ability to perform proactive power management of the hosts. This is achieved using the vCenter feature called distributed power management or DPM.
Distributed resource scheduler - DRS
DRS is vCenter's load balancing ...