OPC HDA Server - query limit

[vince2e]

Hey guys,

I'm getting the following errors when I try to query over 77,000 values from an OPC HDA Client.

WCCOAopchdasrv(2), 2018.01.31 14:24:07.129, PARAM,SEVERE, 143, Query aborted with the following error: HistQuery, constructAnswerMsg, archive request returns an error - too many values!
WCCOAopchdasrv(2), 2018.01.31 14:24:07.194, PARAM,SEVERE, 54, Unexpected state, DpQueryWFA, callBack, qitem->m_lError: 2


Are there any known limits of the OPC HDA Servers or benchmark tests that specify what the limits are? I can't find any in the documentation.
Also, I've increased the limits on the following configs:

maxBcmBufferSize
bcmBufferLimitTimeout
queryMaxValues

Local OA support doesn't have any answers for this problem.

Please note, I've ran into a similar issue on Trend objects where there were "too many values" queried from the archive. I'm starting to think this is a bug or poor memory management.

[leoknipp]

In the FAQ section you will find an explanation for this log message
https://portal.etm.at/index.php?view=it ... &Itemid=54

Even if the FAQ refers to the UI the information also fits the OPC HDA server as the log message is written when a historical data requests is stopped by reaching a query limit.

Best Regards
Leopold Knipp
Senior Support Specialist