The OPC UA server under specific circumstances does not use PublishRequests in the order First-In-First-Out

The OPC UA server under specific circumstances does not use PublishRequests in the order First-In-First-Out

Summary

Under specific circumstances it may happen that the OPC UA server does not use PublishRequests from the queue in the order First-In-First-Out. This may result in the oldest PublishRequest expiring while the newest received PublishRequest is used.  

Description

Under specific circumstances it may happen that the OPC UA server does not use PublishRequests from the queue in the order First-In-First-Out. This may result in the oldest PublishRequest expiring while the newest received PublishRequest is used.  

Solution

An issue has been addressed in the OPC UA server for the process gateway and the OPC UA server for zenon logic, where under specific circumstances with multiple subscriptions created, the OPC UA server would use the last received PublishRequest instead of the oldest received PublishRequest.   Now the OPC UA server always uses the oldest received PublishRequest from the queue.

Issue Number: 36769
Fixed on Date: 18.7.2016
Versions: 7.20 0 BUILD 30230 | 7.50 0 BUILD 30617

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