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14 Dec 2020 11:55 #9272 by support
Thank you for update.

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14 Dec 2020 10:23 #9270 by NAX
Hello again,

I had a stress verison running for a while (many unsubscribes and re-subscribe repeatedly), and it seems that after a little while, it seems to release some of the resources again. It did a high peek in ram, but after a little period of time it released many of the resources and stabilized.

So I think you are correct about it just being a .NET related issue :)

Thanks for the assistance :)

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16 Nov 2020 08:30 #9150 by support

The .NET manages memory on its own, and I can tell you, in one instance we had to observe the memory for a week, to determine that there is no memory leak. I will certainly recommend no less than 72 hours. And, you must be able to induce a a continuously growing trend.

This said, of course, you might be facing a genuine issue. For us to be able to diagnose it, are you able to put together a complete, self-contained example that shows the behavior?


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13 Nov 2020 13:22 #9143 by NAX

I'm using QuickOPC 5.53.405.1 for a UA and DA client.

The program uses a collection of sets of tags, and each tag in each set subscribe to 1 or 2 monitored item with different OnDataChanged events depending on being 1 sub or 2 sub.

However, when there are changes to either EndPoint or Node, which can be changed from a user interface, the program unsubscribes all monitored items and then disposes client and makes a new tag object.

However, I noticed after som testing that it kept taking more memory, the more tags it had to replace and amount of times it was happening.
I kept making changes to make it climb in memory over the course of a day, and then kept it running without changes over night, to see if it dropped again. But when I checked the next morning it hadn't dropped.

I also tryed upgrading the project from .NET Framework 4.5.2 to 4.8, and updated to 5.58.451.1 through the NuGet manager. But the scenario persists.

The only pointer I could find was through the Diagnostics tool in VS 19, where I noticed some Array List which keeps increasing in size, in version 5.53. But in 5.58.451.1 there are some LinkedLists and Dictionaries that keeps increasing in size?
On of the lists are LinkedList<Opc.Ua.NotificationMessage>,

Best regards

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