Diagnosing EE/System problems

Check the following: (order depends on issue)

JVM
- JConsole (memory, cpu utililzation, threads, deadlocks)
- JStack (blocking, locks, what are threads doing) or kill -3

Logs
- Load Balancer log
- Access Log
- Query Log
- GC log - been burned by this one twice
- Server logs (JBoss, server, error, etc.)
- Log4j logging latency - use async appenders

Virtualization issues (VMWare)
- OS scheduling latency
- Network latency
- Filesystem latency

OS stats
- top
- ntop
- iostats

External System Latency
- databases
- AD
- EMail
- MOM/JMS
- Web Services
- network storage
- etc.

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