1. A method for converting heavyweight instances to lightweight instances, comprising: receiving an indication to convert one or more heavyweight instances to corresponding one or more lightweight instances; creating, using a processor, one or more sharable parent instances; creating one or more lightweight instances; for each lightweight instance, designating one of the one or more sharable parent instances as a parent to create a lightweight composite instance; wherein each of at least a subset of the one or more sharable parent instances is shared by two or more lightweight instances and the created lightweight composite instances are configured to provide the functionality provided by the one or more heavyweight instances.