Resource pools are logical containers that can be used to allocate compute resources to a group of VMs (or child resource pools). The configuration options are exactly the same as with single VM—you can assign different reservations, shares, or limits for both CPU and memory resources on the resource pool, but compared to individual assignment to the VMs, resource pools provide a better and smoother management process and added scalability for the control of resources for groups of VMs.
Please note that resource pools can be used only in DRS-enabled clusters.