Heap Capacity Initial, final, and peak sizes allocated for various organizational spaces in the heap.
Peak Usage of Capacity The highest percentage of actual use by the application of the heap at its final capacity configuration. A rule of thumb for optimal utilization would be to have the eden space at 100% with the survivor and old spaces showing some reserve capacity, depending on the application.
GC Activity Summary In this example, a comparison of scavenges and full garbage collection of the old and permanent generations, showing number of GC occurrences, duration, and memory usage for each GC type displayed.
Duration of the Measurement The approximate, elapsed, wall clock time for the entire data collection.
Measurement Enabled and Measurement Disabled “Measurement enabled” refers to the total time during which zero preparation GC data collection has been activated during the session thus far. “Measurement disabled” refers to the total time during which no data was collected (zero preparation GC data collection is not in use). These values are visible on this tab when zero
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