VerboseGC Analysis

Get a sample Java Programme to raise OOM Exception.

Open the VerboseGC to analyze using JVisualVM.

       YoungGen Space :  Short lived objects

       OldGen Space     :  Long lived objects

       GC: Minor Collections

       FullGC: Major Collections

     

Always read the GC or FullGC collections from left to right.

How to Read:

``````````````````

Memory BEFORE --> Memory AFTER ( TOTAL CAPACITY )

Frequent major collections ( FullGC) --> High JVM Pause time --> Performance Degradation

Always determine your java heap footprint retention after a major collection (FullGC)

The Bigger the heapspace higher the elapsed time of the major collections (with same hardware specs).

Observer the BreakDown of heap at the END of VerboseGC File.