Establish a well-articulated and clear problem determination methodology for the solution that you will deploy to your production environment.
This means maintaining a document of your problem determination methods and practicing the documented methods on a consistent basis.
It is recommended that you document your solution-specific problem determination methodology in an operations manual. This operations manual should contain the following types of information pertaining to solution-specific problem determination:
By using an established format you can achieve consistency in recording your observations. Excel spreadsheets are common “observational reporting tools".
Before implementing a trace, make sure that the trace will not make matters worse. It is not appropriate to “enable everything”. Take care when enabling trace, as trace specifications should be appropriate for the observed condition. Use intelligent situational analysis to collect the correct diagnostic information. If you are unsure how to implement the correct level of tracing, contact IBM® support.
Verbose garbage collection (GC) data provides extensive details about how the GC is running for a specific application. This can be useful for analyzing performance problems and tuning the GC settings for the application.
Heap dump capability is a feature of the IBM JVM that prints a record of all objects in the Java™ heap to a text file.
The size and address of each object are recorded, as well as the addresses of all objects that it references. This information can help you understand which objects are responsible for taking up large amounts of memory.
Performing problem determination by analyzing the javacore file is an effective means of determining root cause of error conditions that might occur in an IBM Java virtual machine (JVM).
Treat your solution-specific problem determination documentation as a living document and maintain and update it as often as new observational practices are learned from functional and system test.