Java Heap Dump: Are you up to the task?

If you are as much enthusiasm as I am on Java performance, heap dump analysis should not be a mystery to you. If it is then the good news is that you have an opportunity to increase your Java troubleshooting skills and JVM knowledge. The JVM has now evolve to a point that it is much easier today to generate and analyze a JVM heap dump vs. the old JDK 1.0 – JDK 1.4 days. That being said, JVM heap dump analysis should not be seen as a replacement...

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java.lang.OutOfMemoryError – Weblogic Session size too big

A major problem was brought to our attention recently following a migration of a Java EE Portal application from Weblogic 8.1 to Weblogic 11g. This case study will demonstrate how you can analyze an IBM JRE Heap Dump (.phd format) in order to determine the memory footprint of your application HttpSession objects. Environment specifications (case study) -         Java EE server: Oracle Weblogic Server...

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Memory Analyzer download

Memory Analyzer (MAT) is an extremely useful tool that analyzes Java Heap Dump files with hundreds of millions of objects, quickly calculate the retained sizes of objects, see who is preventing the Garbage Collector from collecting objects, run a report to automatically extract leak suspects. Why do I need it? OutOfMemoryError problems are quite complex and require proper analysis. The tool is a must for any Java EE production support person or developer who requires to investigate memory leak and / or to analyze their application memory footprint. Where can I find tutorials and case studies? You will find from this Blog several...

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HPROF – Memory leak analysis tutorial

This article will provide you with a tutorial on how you can analyze a JVM memory leak problem by generating and analyzing a Sun HotSpot JVM HPROF Heap Dump file. A real life case study will be used for that purpose: Weblogic 9.2 memory leak affecting the Weblogic Admin server. Environment specifications ·         Java EE server: Oracle Weblogic Server 9.2 MP1 ·        ...

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Class loader memory leak debugging tutorial for IBM VM

This article will provide you with a step by step tutorial on how you can pinpoint root cause of Java class loader memory leak related problems. A recent class loader leak problem found from a Weblogic Integration 9.2 production system on AIX 5.3 (using the IBM Java VM 1.5) will be used as a case study and will provide you with complete root cause analysis steps.    Environment specifications (case study) ·       ...

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