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opc ua client get value very slow
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Stitch35
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10/24/2018 - 01:43
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I have 1000 tag 

every 1 sec I want to read 1000 tag

 

foreach (var eachTag in Tag)
{
    DataValue read = session.ReadValue(eachTag.NodeId);

}

1000 tag Time elapsed: 00:00:15.1166664

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Paul Hunkar
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10/25/2018 - 13:39
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Why would you want to read 1000 tags, why not use subscriptions?  OPC UA is designed to have a very efficient system for getting the latest value of a variable.  Reads are used to get static information from a system, or to get a single value (i.e. not something that is updated periodically).

In any case if you are reading – why issue a 1000 single point reads vs one read for 1000 points?  you have created a lot of round trips to the server.

  So the last question would be what server are you communicating with?  what is the network speed?  a small embedded device will perform very differently from a large server.

Paul Hunkar - DSInteroperability

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