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Memory leak issue cause by OpcLabs.QuickOpc

09 Jan 2020 17:54 #8128 by support

how do you know that there is a memory leak? Have you observed the memory growing for really long time (many hours) or until it's all consumed? In .NET, the memory may remain allocated for rally long time, the operation of the garbage collector are not deterministic. Please provide a PerfMon graph/data showing the leak.


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09 Jan 2020 11:42 #8126 by KrisSik

I got a memory leak issue and the problem I think could be caused by the OpcLabs library, because a huge part of the memory used by the application is allocated by the unmanaged resources. The exception (listed below) throws ≈ 1 time per minute.
OpcLabs.EasyOpc.Engine.NetApiException: An exception occurred during processing in a NET API OPC Data Access client. The inner exception contains details about the problem. ---> System.Net.WebException: The underlying connection was closed: A connection that was expected to be kept alive was closed by the server.
   at System.Web.Services.Protocols.WebClientProtocol.GetWebResponse(WebRequest request)
   at System.Web.Services.Protocols.HttpWebClientProtocol.GetWebResponse(WebRequest request)
   at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)
   at OpcXml.Da10.Service.GetStatus(String LocaleID, String ClientRequestHandle, ServerStatus& Status)
   at OpcXml.Da.Server.GetStatus()
   at Opc.Da.Server.GetStatus()
   at OpcLabs.EasyOpc.Implementation.NetApi.DataAccess.NetApiOpcDaServer.GetStatus(Boolean doOnlyIfGoodStatus, Exception& exception)
   --- End of inner exception stack trace ---
I am using OpcLabs.QuickOpc 5.55.433.1 in my .NET Framework 4.7.2 application, which is running on Microsoft Windows Server 2008 R2 Enterprise.
Any ideas regarding this?

Best regards,

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