1. A system for managing software product instance placement, the system comprising: a plurality of physical computing resources available for utilization; a specification of a hierarchal arrangement of the software product instances, the specification specifying: capacities of the physical computing resources, resource demands of virtual machines, which type of the physical computing resources the virtual machines are permitted to execute on, and whether the virtual machines are permitted to move to a different physical computing resource; a placement server to communicate with a client, wherein the client is a clustered middleware system, the client seeking to use a portion of the plurality of physical computer resources to execute the software product instances, the placement server configured to receive resource utilization parameters from the client, the resource utilization parameters including the specification of the hierarchal arrangement of the software product instances, the placement server configured to assign the portion of the plurality of physical computer resources to the software product instances based on the resource utilization parameters and the physical computing resources available for utilization; and a communication port at the placement server, the communication port configured to receive the utilization parameters in a standardized form, the utilization parameters specifying whether virtual machine instances can be moved from one physical computer to another physical computer; and placement triggers configured to initiate an assignment of the portion of the plurality of physical computer resources to the software product instances based on a predetermined condition unless the utilization parameters specify the portion of the plurality of physical computer resources cannot be assigned to the software product instances; and wherein the placement server is stateful, such that the portion of the plurality of physical computer resources assigned to the software product instances is further based on computer resource assignments to other clients; wherein the predetermined condition is a time interval; and wherein the placement server is shared by multiple clients in a cloud infrastructure.