Clearing data objects used to maintain state information for shared data at a local complex when at least one message path to the local complex cannot be recovered

摘要

Apparatus for recovering resources in a data processing system having at least one CPC including at least one central processor for executing instructions arranged in programs for processing data, a main storage for storing data and said programs, and including a structured external facility, and multiple message paths connected between the CPC and the structured external storage facility for passing data, messages and responses therebetween. The CPC includes multiple indicators, one for each message path, and vectors which indicate the validity of data shared by the main storage with the structured external storage facility. A message path status facility determines if any of the message paths become unavailable. If any of the message paths is determined to be unavailable, its indicator is set, and a recovery of resources is started. The status of each message path is tested. If the message path is not available, an attempt is made to make it available to the central processor for passing data, messages and responses. If all message paths connecting a CPC to the SES become unavailable, the vectors are cleared indicating that the shared data is no longer valid.