Sporadic Deadlocks and Power Chart

We have noticed sporadic deadlocks which seem to point to the Power Chart, specifically, the PowerChartModelDelegate$TagHistoryFetch.fetch() method. Curious to know if anyone else has noticed this.

The deadlocks are on the SQL server side, not the Ignition side - you should investigate what’s holding locks on that table for a long period of time, and why (it’s likely data being inserted; check index fragmentation, which is a common problem with our historian tables in MSSQL).

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Sorry - yes, inserts into the historian are the cause of the locks. The Power Chart just exposes them as it attempts to query the historian. I will check the indexes and verify the frequency of our re-builds.