Why are My Time Stamps on Shared Variables, LabVIEW DSC Alarms and Events and Data Logged to the Citadel Database Incorrect and Unpredictable?Primary Software: LabVIEW Development Systems>>LabVIEW Professional Development SystemPrimary Software Version: 8.5 Primary Software Fixed Version: N/A Secondary Software: N/A
Problem: My time stamps on shared variables, LabVIEW DSC alarms and events and/or data logged to the Citadel database are incorrect. They increase or decrease unpredictably in time. What is happening? Solution: If you are seeing unpredictable, incorrect time stamps on your shared variables, LabVIEW DSC alarms and events and data logged to the Citadel database, this is unexpected behavior. The primary symptom is that, with the Time Service running, the time stamps returned for Variables will be incorrect. The timestamps will increase rapidly, reaching out to several months ahead of the current wall clock time. After a period of about 60 seconds (wall clock time), the timestamp will reset to the time shown on the system clock, and then begin increasing rapidly for another cycle. If you are using LabVIEW DSC, you may also see an increased CPU usage in the Tagger and Citadel services. This issue is related to the AMD Multi-Core/Multiprocessor issue discussed in the knowledge base AMD Multi-Core/CPU Systems Can Cause Unexpected Behavior in NI Driver Software. This linked KB discusses all the reasons and fixes for this issue. Note: This issue has also been known to cause crashes of the shared variable engine when logging shared variables to the Citadel database with LabVIEW DSC. Related Links: KnowledgeBase 4BFBEIQA: AMD Multi-Core/CPU Systems Can Cause Unexpected Behavior in NI Driver Software Attachments:
Report Date: 01/17/2008 Last Updated: 01/02/2009 Document ID: 4HGE270W |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
