Abstract: A system and method for determining and managing risk impact of service downtime includes defining a process structure of one or more process types, services the process structure employs and a distribution of the services' time durations. Process usage data is collected for each type of process, and risk is estimated based on penalties and expected deadlines for each process. For a service change and outage of a given length of time, an optimal change window is determined with respect to a minimized impact on the process based on the estimated risk.

Abstract: In order to control access to resources of a data processing system, a priority code is determined for an access request to at least one resource. A comparison code for granting access to the at least one requested resource is determined concerning an alternative use of the resource. For a totality of resource requests to the data processing system, an extreme value for a sum is determined via products of a corresponding priority code and of a number of resource accesses which can be granted in each case, taking into account a maximum capability of a requested resource. For a resource request, it is checked whether the priority code and the comparison code show a predetermined mutual relation. Access is granted depending on the extreme value determined and on the result of the check.