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One or More opc server disconnect ,WriteMultipleValue() slowly

17 Sep 2023 14:01 #12155 by support

1 and 2. Are you addressing multiple servers inside one WriteMultipleXXXX operation? If so, the "writes" are generally performed in parallel, but because the WriteMultipleXXXX API is synchronous, all results must be delivered together, meaning that if there is a "delaying" problem connecting to at least one server, the whole method call will be delayed, until we have some result for all elements of the operation. This is by design. Same happens with multiple tags inside on server - if the server needs more time for one of them, the whole method call has to wait until we have all results.

If you are not addressing more servers inside one WriteMultipleXXXX , and still get unexpected delays even from servers that are otherwise "OK": Have you looked at the total CPU usage on the machine, and CPU usage of the process?

3. Need to know the details of the failures - what was the error message?


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15 Sep 2023 09:02 - 15 Sep 2023 09:05 #12141 by xpycy001
Dear support:

1 Subscribing to more than 80 servers in a Client.exe, with one or more OPC server disconnected or offline, affects the performance of EasyUaClient.WriteMultipleValue , and often in write operations used several hundred milliseconds or 5 to 10 seconds or more

2 At the same time, I also noticed that if there are any problem tags, they can also affect the performance of the WriteMultipleValues()

3 Simultaneously, some writeMultipleValue() failures were found

I would like to confirm if the above issue is normal or if there is any way to solve it

Other information is as follows:
1 Windows server2019
2 opcUA Version Info: OpcLabs. QuickOpc 5.71.334
3 The main program is:. NET 7.0 console exe
4 used One EasyUaClient instance, subscribe & WriteMultipleValue, one time write about 10~50 tags value
5 OpcUaClient has subscribed to approximately 80 OpcServers with approximately 5000 Tags

2023-09-15 17:01
Last edit: 15 Sep 2023 09:05 by xpycy001.

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