java - JVM keeps calling garbage collector for no apparent reason

Question

While testing MaxFreeHeapRatio and MinFreeHeapRatio I found the following situation:

Application heap profiling

Garbage collector activity profiling

So, the JVM keep executing the garbage collector even though there is lots of free memory available.

I'm using the following flags:

-Xms512m
-Xmx15636m
-XX:MaxHeapFreeRatio=70
-XX:MinHeapFreeRation=20

Any idea of the reason for this behavior?