2 Replies Latest reply on Nov 28, 2018 9:10 AM by Martin_Guardia

    PI AF Counters Issues

    Martin_Guardia

      Hi Guys,

       

      I would like your support in order to understand the following:

       

      1. When I am using counters in PI AF, I realized that sometimes i am not able to use "Save Output history -No-". Due to this is only a semaphoring counter i don´t need to store that value but, I am not able to choose the option.

       

      I tried to recreate the attribute but, for some reason PI AF is not updating and executing this analysis.

       

      Thanks a lot,

        • Re: PI AF Counters Issues
          sraposo

          Hi Martin,

           

          I'm suspecting that you are referring to Asset Analytics, and more specifically Roll Up analyses?

           

          The recommended output of a Roll Up analysis is an attribute with a PI Point data reference (Save Output History). The Roll Up analysis does not support the Analysis data reference (No Output History) for performance reasons.

           

          This is explained here: KB01586 - The Analysis Data Reference: Use Case, Configuration and Caveats

           

          And we have the enhancement request on our feedback website here:

           

          Allow Rollup analysis to output to to an Analysis Data Reference – User Feedback for OSIsoft Products and Services

           

          It is possible to output to an attribute with a data reference of <none>, but this is NOT recommended, especially if you are running an AF Server version before 2017 R2. Even in the newer versions, this is still not recommended. The reasons are that frequent writes to attributes with a data reference of <none> (read static attribute) can cause performance issues in the SQL back end and thus affecting the entire AF Servers performance.

           

          Hope this helps,
          Seb

            • Re: PI AF Counters Issues
              Martin_Guardia

              Hi Sebastien,

               

              I appreciate your taking the time to answer my question.

              That´s correct, I´m using Asset Analytics and Roll Up Analyses, specifically.

              We have PI HA and AF Server 2017 R2.

              PI AF Versions.PNG

              In fact, I´ve been using Roll up Analyses taking into account Data Reference: none. As you said, it works but, we i was trying to use in another element and, it is asking for "Save Output History (Yes)", which in our case shouldn´t been necesary due to it is counting numbers of products on-spec, only. We are using semaphores on a production main display based on the current analysis, it is not necessary their history, itselfs. Just to see the numbers.

              Numbers on-specs.PNG

              On the other hand, I understand that performance issues could come out in the SQL back end and thus affecting the entire AF performance. And my question in this point is: Is there any option to minimize this impact using "Periodic Schedule" trying to set up in different periods the triggering action. Could it help us whether we would change the default period?