monitoring JMS connection pool using JMX/PMI

[Anbu]

I have created a JMX/PMI extension and configured it to collect JMS connection pool metrics from WebSphere.
In the WebSphere Admin Console, the JMS connection pool size is set to 30.

However, in Dynatrace I notice something strange:

• The free pool size and pool size always show the same values.

• When I change the timeframe to Last 2 hours, the values are different.

• But when I select Today, the values change completely and do not match the 2-hour values.

Because of these inconsistent values, I am not sure whether my PMI/JMX extension is working correctly.

Steps I followed:

1. Dynatrace Managed

2. Settings → Monitoring → Monitored technologies

3. Add new technology monitoring

4. Add JMX/PMI extension

5. Use JMX/PMI Extension Editor

6. Under the J2C module, I selected the metrics for Pool Size and Free Pool Size

I am using WebSphere with MQ.
Could you please guide me on how to verify whether my JMX/PMI extension is capturing the correct JMS connection pool metrics?

[sujit_k_singh]

When using a JMX/PMI extension for WebSphere JMS connection pool metrics, the behavior you’re seeing (values changing with different timeframes) is usually due to aggregation and resolution differences, not an extension failure. Dynatrace aggregates data differently for “Last 2 hours” vs. “Today” (rollups like min/avg/max), so the displayed values can vary.
To verify your extension is working correctly: Go to Metrics → Data Explorer -> Select your custom JMX metrics (like PoolSize, FreePoolSize).
Set the resolution to 1 min or 5 min and compare with WebSphere Admin Console values.