Method of Validating a Control Block in a Sysplex Environment.
Original Publication Date: 2004-Apr-22
Included in the Prior Art Database: 2004-Apr-22
This Invention Disclosure Publication discloses a fast and effective method to validate a control block address that can become obsolete after a restart of a system in a sysplex environment that provides message and data sharing.
Method of Validating a Control Block in a Sysplex Environment .
In a sysplex environment that provides message and data sharing, messages can be put on a common storage media to be processed by any systems. In some occasions, output from these messages that are processed by a sharing system become obsolete across a system restart of an inputting system. A mechanism is needed to validate output messages that can be from a previous execution of an inputting system to avoid causing a storage exception.
A message is uniquely identified by a message token. A message token consists of a time stamp and a control block address which points to the data structure that represents an input message. This Invention Disclosure Publication discloses a validation method of a control block address using a message token.
Instead of scanning the entire allocated control block chain for the control block address in a message token, this validation method compares the time stamp in a message token with the inputting system restart time. If the time stamp in a message token is greater than the inputting system restart time, the message token is considered valid. This means the output message is not obsolete. The control block address in the message token that represents the input message can safely be used to locate the control block directly without causing a storage exception. If the time stamp in a message token is less than or equal to the inputting system restart time, the message...