Abstract: Provides a method for increasing the connectivity of I/O resources to a multiplicity of operating systems (OSs) running in different resource partitions of a computer electronic complex (CEC) to obtain sharing of the I/O resources among the OSs of the CEC, including channels, subchannels (devices), and control units (CUs). The invention provides image identifiers (IIDs) for assigning resources to the different OSs. Each shared I/O resource has a sharing set of control blocks (CBs) in which a respective CB is assigned to (and located by) a respective IID of one of the OSs. Each of the CBs in a sharing set provides a different image of the same I/O resource. The different CB images are independently set to different states by I/O operations for the different OSs, so that the OSs can independently share the same I/O resource.

Abstract: The invention disclosed and claimed herein provides a method for a virtual machine, which maps to the V=R region of a host machine's address space, to resume program execution successfully when the host operating system terminates and subsequently restarts successfully after the occurrence of a system incident. The system incident brings the computer system down, but with a reasonable chance that the system will be able to bounce. A bounce occurs when the host operating system nucleus is reinitialized or refreshed. The virtual machine will be allowed to survive the system incident as long as its integrity can be maintained, i.e. as long as its status and in-progress work can be preserved.