splatch commented on issue #1896: URL: https://github.com/apache/plc4x/issues/1896#issuecomment-2486332384
> It is working for me, but I think there are some problems with subscriptions with the current PLC4X code, the code is polling constantly once per second @codekundan @hyslopc AFAIR you can try to adjust that, you need to use cyclic subscription. Cycle duration used for first tag will dictate cycle time for polling OPC-UA server: https://github.com/apache/plc4x/blob/v0.12.0/plc4j/drivers/opcua/src/main/java/org/apache/plc4x/java/opcua/protocol/OpcuaProtocolLogic.java#L768 If not provided it is assumed to be 1s. OPC-UA protocol itself requires publish request to receive publish response with changed tag values, so you can reduce load, at the cost of bigger delay since possible value change. > I don't think there's any time limit on subscriptions, but they are only valid for the lifetime of the channel, and there is a channel-lifetime setting, which defines the maximum amount of time the channel will be open (in fact the server must leave the channel open 25% longer than this). Default is one hour, so after 75 minutes, you will be disconnected, unless you specify a higher channel-lifetime Channel lifetime is declared by server, when secure channel is open or renewed. For that reason we do not have a setting for that, we just rely on what server wants. If you suspect any resource leak then renewing of channel might possibly be guilty (AFAIR it was guilty of some thread leak before), other place could be subscription handles which also need to submit asynchronously a publish request, beside your application logic. Look at these two places (OpcSubscriptionHandle.java and SecureChannel.java). If you have a lot of connect/disconnect cycles then both will fail to properly manage threads started within their internals. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
