My company recently purchased Ignition, and I've been converting all the HMI's in our plant over. I recently received some complaints about lag and slowness. I looked at the performance dashboard and found the CPU Usage was indeed very high. This was recent because I've been monitoring the usage as I convert more areas.
I did a fair amount of reading on other forum topics about garbage collection and and some other things to look at with the threads. Restarting the Ignition Server did not resolve the High CPU Usage at all. It came right back.
We're running the old HMI system in parallel, so I can be very aggressive with troubleshooting the new system. I started disabling projects, database connections, and PLC connections until I finally pegged it to the Core Historian I was using for a few Trend Charts. After disabling the historian and re-enabling everything else, I was less than 10% CPU Usage.
I have 30 Historical Tags set up for 1 Second Sampling. For the Core Historian itself, I set the Partition Interval to "Hours" and the Maintenance Age to 6 Hours. I realistically need only 30 minutes of chart.
I played with the Partition Interval and the Maintenance Age but no matter what I changed, the CPU Usage shoots right back up to > 80% when I re-enable it. I configured the Historian probably 2-3 months ago and it had been running fine. The area of use was completed, so I haven't added any tags to that Historian in that last 2-3 months either.
Ignition Version is: 8.3.3 (b2026012009)
Is there something obvious I'm missing or doing wrong?