WebSphere Application Server V7.0: Concepts ... - IBM Redbooks

– Proxy counters
– ORB counters
– Transactional counters
– Workload management counters
► System resources
– Processor usage
– Total free memory
– Components that are controlled outside the WebSphere environment but
that are vital in healthy application state
Note: PMI offers the custom PMI application programming interface (API).
This enables you to insert your own custom metrics and have them captured
and available to the standard monitoring tools.
When determining which metrics to capture, you can select from the following
monitoring statistics sets:
► Basic (enabled by default)
– J2EE components
– CPU usage
– HTTP session information
► Extended (basic +)
– WLM
– Dynamic cache
► All
► Custom (select your own mix of metrics)
The Java Virtual Machine Tool Interface (JVMTI) is a native programming
interface that provides tools with the option to inspect the state of the JVM. This
interface was introduced with JVM V1.5. JVMTI replaces the Java Virtual
Machine Profiling Interface (JVMPI), which is supported in WebSphere
Application Server, Version 6.0.2 and earlier. The JVMPI interface became
deprecated in WebSphere Application Server Version 6.1. Both interfaces
(JVMTI and JVMPI) provide the ability to collect information about the JVM that
runs the application server. The statistics gathered through the JVMTI are
different between the JVM provided by IBM and the Sun HotSpot-based JVM,
including Sun HotSpot JVM on Solaris and the HP JVM for HP-UX.
Enabling the JVMTI involves enabling the JVM profiler for the application server
and selecting the appropriate metrics using the Custom settings.
Chapter 7. Performance, scalability, and high availability 269