Crash When Opening More Than One OPC UA Instance in LabVIEW 2024 Q3

Updated Dec 10, 2024

Reported In

Software

  • LabVIEW 2024 Q3
  • LabVIEW OPC UA Toolkit

Issue Details

If I initialize two LabVIEW OPC UA Toolkit instances like Client Connect.vi or Server Create.vi, LabVIEW 2024 Q3 crashes without error, i.e., the window simply disappears. 

 

How can I get around this issue?

Solution

This is a bug that has been reported. It affects only LabVIEW 2024 Q3.

 

When an OPC UA instance is first initialized, it calls a certain resource. When more than one instance is initialized at the same time, both instances aim to load the resource and this causes a race condition thus crashing LabVIEW. However, this issue does not happen once this resource is already in memory, i.e., has been successfully loaded onto memory by a single OPC UA instance's initialization.

 

To get around this issue, you can either:

  • Serialize the initialization of OPC UA instances by wiring error terminals in sequence, or by calling them sequentially instead of in parallel. 
  • Load the resource into memory by calling a single OPC UA instance first, and then continue calling them in parallel if needed.