Performance Monitoring Infrastructure (PMI)
A typical Web system consists of a Web server, appserver, and a database. Monitoring and tuning the appserver is critical to the overall performance of the Web system.
Performance Monitoring Infrastructure (PMI) is the core monitoring infrastructure for WAS and WebSphere family products like Portal, Commerce, and so on. The performance data provided by WebSphere PMI helps to monitor and tune the appserver performance.
PMI provides a comprehensive set of data that explains the runtime and application resource behavior. For example, PMI provides...
- database connection pool size
- servlet response time
- EJB method response time
- JVM garbage collection time
- CPU usage
- etc...
This data can be used to understand the runtime resource utilization patterns of...
- thread pools
- connection pools
- CPU usage
- Servlet response time
- JDBC query time
- JavaServer Pages
- enterprise beans
Use PMI data, the performance bottlenecks in the appserver can be identified and fixed. For instance, one of the PMI statistics in the JDBC connection pool is...
Number of statements discarded from prepared statement cacheThis statistic can be used to adjust the prepared statement cache size in order to minimize the discards and to improve the database query performance.
PMI data can be monitored and analyzed by...
- Tivoli Performance Viewer (TPV)
- Other Tivoli tools
- Your own applications
- Third party tools
TPV is a graphical viewer for PMI data that ships with WAS. Performance advisors use PMI data to analyze the run-time state of the appserver, and provide tuning advice to optimize the appserver resource utilization.
Performance management tools like Tivoli Monitoring for Web Infrastructure and other third party tools can monitor the PMI data and generate alerts based on some predefined thresholds.
Sub-topics
PMI architecture
PMI and J2EE 1.4 Performance Data Framework
PMI data classification
PMI data organization
PMI data collection
Related Reference