You didn't do any check for bad data. The calculation will fail (and stops) if one of the tags contains bad values like I/O timeout or No Data
True, but the skippings appear where data is present and good. And the "GmsTagAvg" works on the same data and succeeds where the first equation fails? We will add the badval check later.
How is this Analysis scheduled?
If it is natural scheduling, which are the input triggers?
What's the setting for the resulting timestamp (Advanced button)?
I see blue markers everywhere I would expect results. Maybe it's not that obvious to someone like me not as familiar with what's expected here like you.
Would you be able to mark those areas (times) where you are missing results?
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My first thought: is load shedding enabled? By default it is, and it might drop events if the analytics processor is overloaded: https://livelibrary.osisoft.com/LiveLibrary/content/en/server-v9/GUID-2B4D156F-8895-4DA0-BD60-78153BE2AE16
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This makes sense, cause ideally the analysis would never randomly skip unless the processor is heavily loaded at that time.
@lars you could monitor the analytics and see if the skip happens during processor overload
Hmm I have this entry in the configuration:
Shouldn't it be "IsLoadSheddingEnabled" and not "LoadSheddingEnabled" ?
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That's what I understand from the resource linked by Roger. I would assume that a wrong keyword in the configuration will make PI Analysis Service fall back to the default: IsLoadSheddingEnabled = true
I am still uncertain about the issue you are seeing. Would you mind adding markers to the screenshot you posted earlier.
Vinit made a great suggestion: Verify with the PI Analysis Service -> Evaluation Skipped Count performance counter if PI Analysis Service is skipping calculations. You may want to utilize the good old PI Interface for Performance Monitor for this purpose and also want to collect additional performance counters of the PI Analysis Service into PI Points.