Garbage Collection

Our Agent gets these timings either directly from the JVM or through JMX measures. You can look at the details of the Measure Definition to see which JMX measures we are actually collecting - or - you can also create new Measures in case the ones we deliver out-of-the-box are not sufficient

Tuning is a different topic - here I suggest you read our online java performance book. it has a chapter on Memory Management

I enable gc logging on our server and then compared it to the numbers in the host dashboard GC times. The GC Times shown by dynatrace was something like this..

It shows absolute GC times of 10 to 15 seconds.

However in the GC log between 2:00 and 2:15pm, the totalms has never gone over 1 second. How is it calculating those numbers?

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