1. A method comprising: identifying, by a processor, at least one physical computing system with available computing resources; adding, by the processor, the identified physical computing system to a cloud; classifying a plurality of physical computing systems of the cloud into a plurality of virtual groups in view of a particular usage of the cloud and computing resources; maintaining multiple group records to identify the computing resources, the multiple group records comprising identification of the plurality of virtual groups and the plurality of physical computing systems; receiving a request from a requester to instantiate a virtual machine in the cloud, wherein the request comprises a specification of the virtual machine and requirements for the computing resources; selecting, by the processor, a virtual group from the plurality of virtual groups in view of an identity of the requester and at least one of: (i) the specification, (ii) a classification of the plurality of physical computing systems, or (iii) the multiple group records; and allocating, by the processor, a physical computing system in the virtual group to the virtual machine.