The test is writing a value to the variable corresponding to each monitored item in the test. In case, we have around 100 variables in the address space, including all data types, and Max. Supported MonitoredItems in the configuration is defined as 1000, will result in the CTT to subscribing 10 times to each variable.

This leads it to write 10 times to each variable. For other DataTypes it is not a real problems, but for GUID, GUIDArray, XmlElement and XmlElementArray types, it seems to use different values, so writing 10 different values for each. Now, this leads into 10 different samples with different timestamps.

As the MonitoredItems are defined with SamplingInterval=50 ms and QueueSize=2, these variables will have 2 samples to send back to the client, whenever the handling of the write takes more than 50 ms in total.

The test should be fixed so that it writes only one value to each variable, even when the same variable is monitored by several monitored items.