Interdicting I/O and messaging operations from sending central processing complex to other central processing complexes and to I/O device in multi- system complex

摘要

In a multi-system complex having central processing complexes (CPCs) and subsystems, a hardware facility for prompt interdicting I/O and message operations. A CPC or subsystem failure causes as interruption in the availability of the data bases to the attached network of terminals. Often such networks have thousands of terminals. Even a short loss of data is detrimental. Therefore the CPC or subsystem takeover must be accomplished as quickly as possible and the I/O attached to the failing CPC or subsystem must be interdicting to release it for use to the rest of the complex. The disclosed hardware facility provides a mechanism which is program initiated and controlled and which guarantees the prompt completion of the interdiction function.