While checking message logs I am getting below error:
Postevent failed: [-109] Value at This Time Already Exists
Hi prasad Pashte:
Depending on the source of the values this error typically is the result of two conflicting interfaces trying to record a value at the same time. There could be a mis-configuration of the failover between two interfaces, or for example two instances of performance equation scheduler sending values at the same time (Performance Equation Scheduler does not have a failover configuration option). The following KB article most likely will address your question and get you pointed in the right direction toward solving this:https://customers.osisoft.com/s/knowledgearticle?knowledgeArticleUrl=KB01592
I am not able to access this article
Will this have any effect on PI system performance activity.
PI Data Archive (aka PI Server) is very robust. Without knowing the specifics of your situation my bet is there is no performance cost to this error. Logically the PI Data Archive has recorded a value, it evaluates the next incoming value and timestamp then decides does this value already exist at that exact timestamp? It does already have a value at that exact timestamp it then does not record the second redundant value. The pi point will still trend and show a value for that timestamp without any reduction in performance.
Next, I am surprised you don't have access to the article since you do have a PI Square membership, which requires a SSO (single sign on). You might have to reach out to tech support to get that resolved. For your convenience I went ahead and attached a pdf copy of the article in my previous reply above.
In addition to what James Devine has shared, I will say that this -109 error is quite common on PI systems. I've seen it from several sources, including PI-RDBMS and PI-UFL interfaces that are trying to overwrite the same data over and over again. It should be cleaned up but it's not an issue of much concern.
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