Patent attributes
Implementation resources are operated in a manner furthering a particular purpose while excluding use of the implementation resources for other purposes. At least some of the implementation resources have capacity that is usable to implement multiple other resources. The capacity of the implementation resources is allocated in a manner that satisfies one or more conditions on the capacity of the implementation resources that is used. Generally, the capacity is allocated in a manner that reduces the likelihood that resources initiated close in time will fail together should underlying implementation resources fail. The implementation resources may be hardware devices that implement virtual computer systems.