Unable to get Tag Values when request more than 1100 tags together in PCo

[Former Member]

Hi Experts,

We are unable to get Tag Values when Try to query more that 1100 Tags in one shot in  PCo.

Below is the error :

• [ERROR] com.sap.xmii.Illuminator.logging.LHException: Query execution failed due to following: [Tag] : Exception [ParserException] - Parse Error occured in directive number 1, 'Directive #2': Maximum Iteration Loops Occured.

• [ERROR] Uncaught exception from TagsUpdatePcoQuery_0, com.sap.xmii.Illuminator.logging.LHException: Query execution failed due to following: [Tag] : Exception [ParserException] - Parse Error occured in directive number 1, 'Directive #2': Maximum Iteration Loops Occured.

Is there any configuration setting to get this or do i need to modify logic in MII and send limited Tags at once ?

Any help will be highly appreciated.

Thanks

Shashank

[salvatore_castro]

Any insight into what you are trying to achieve is useful here as there may be a better approach/design to your application.  Please also share the version of your MII/PCo installations.

Thanks,

Sam

[Former Member]

Hi Salvatore Castro

We are actually using POc replacing Webservices where in we are requesting more that 1100 tags at a time and getting the valid response.
We are trying to implement the same logic for PCo, so that can be done with minimal cope change.

MII 14.0

PCo 2.3

Thanks

Shashank

[salvatore_castro]

Ok, so what is the frequency of the data request...is it current or historical (interpolate, aggregated, plot, or event) data and what is the tag system that is involved here?  Also, are you using the PCo Connector or the legacy Tag connector to make this request?

In PCo, for the agent do you have the TagQuery -> Cache Mode set to Demand...or something else?

Thanks,
Sam

[Former Member]

Hi,

Request is sent in every 10 mints so that to get the updated value.

This is for Current data using PCo connector.
Cache mode has set as demand.

Thanks

Shashank

[Former Member]

Hi ,

I am also facing same issue.

Can you please suggest me how you have resolved this issue.

Regards,

Hari.

[former_member196557]

Hi Hari,

Which Version/SP/Patch of PCo and MII?

How many tags are you requesting? is there a specific number limit above which the error occurs?

Which Query template in MII:  PCoQuery or TagQuery?

Query for current tag values or some aggregate/historical query?

What error message are you getting from the Query?

What is the PCo Data source?

What is the setting for the Agent Instance Query Tab Cache mode?

What is the setting of PCo Tools->Options->Browsing->Returned Row size?

Regards, Steve

[Former Member]

Hi Steve,

Thanks for your response.

Please check the details.

• Which Version/SP/Patch of PCo and MII?  Answer MII : 14.0 SP5 Patch 11,                                                                                                  PCo : 2.3
• How many tags are you requesting? is there a specific number limit above which the error occurs?  Answer:1200 tags,each tag contains 15 to 20 characters
• Which Query template in MII:  PCoQuery or TagQuery?  Answer :PCo query
• Query for current tag values or some aggregate/historical query? Answer : Current
• What error message are you getting from the Query?

          Answer : [ERROR] com.sap.xmii.Illuminator.logging.LHException: Query      execution failed due to following: [Tag] : Exception [ParserException] -      Parse Error occured in directive number 1, 'Directive #2': Maximum      Iteration Loops Occured.

• What is the PCo Data source?  Answer : PI Historian
• What is the setting for the Agent Instance Query Tab Cache mode?  Answer : Demand
• What is the setting of PCo Tools->Options->Browsing->Returned Row size? Answer : 100

Regards,

Hari.

[former_member196557]

Hi Hari,

First, change the Returned Row Size to a value > 1200, say 2000.

If that does not fix the issue, make sure you have deployed the most recent PCo 2.3 SP06 Patch 2.

If that does not fix the problem, recommend that you update PCo to the latest 15.1 SP02 Patch 7.  Note that with PCo 15.1 there is no longer a license requirement, you can install and run without registering a license file. Also, as you patch/upgrade your current instance, make sure you create a FULL export of the PCo configuration.

Regards, Steve

[swaroop_anasane]

Hi Shanshank,

If it's a Maximum Iteration Loops Occured exception, you might have reached maximum limit. It's better if you can break it in chunks and parse the data. This would rather help you optimize your app.

Thanks,

Swaroop

[Former Member]

Thanks Swaroop,

My understanding is that there must be any parameter in PCo Management which limits the number of Tags browsed at a time. Doing this i don't have to rewrite the logic and can use the existing logic.

Regards

Shashank