11 Replies Latest reply on Mar 7, 2012 1:50 AM by pcombellick

    Concurrency issue with PI Datareference under high load ?




      Hi I have some curious findings in while doing load tests with Visual Studio 2010.


      The test results lead me to the conclusion that there is a threading issue with the PI datareference.


      This is the test scenario:


      Start with 1 user doing requests to an Element attribute value and add 5 users every 25 seconds: Objective is to find the ‘breaking point’ of the server and determine concurrency capabilities of AF.


      This is the observed behavior:


      Configuring the attribute with a constant value results are not blocked


      Configuring the same attribute with a pi value results are blocked  (see figure 2 and 3)




      Question to the forum: Has anybody performed similar test and observed the same behavior and are there any known issues wrt. the PI datarefence ? 




      Figure 1: using AF using a constant attribute value




      Figure 2 Using AF with the PI data reference




      Figure 3: Figure 2 Using AF with the PI data reference, detail view