[CONF] OpenJPA > Fetching Statistics

[confluence]

Fetching Statistics Page edited by Helen Xu Changes (19) h1. Fetching Statistics Open JPA Fetch Statistics Tool monitors persistent field access and determines which fields are never used. This tool can be used to help tune an application. Note: Open JPA Fetching Statistics Tool works with the runtime enhancement. h3. Download Usage instructions: The latest OpenJPA Tools JAR file can be download from the [SNAPSHOT Repository|https://repository.apache.org/content/repositories/snapshots/org/apache/openjpa/tools/openjpa-tools] or can be built from the source code in [svn|https://svn.apache.org/repos/asf/openjpa/tools/trunk] by using Maven 2.2.1 and Java SE 6. h3. Usage bq. This description assumes your application is running the on same machine as JConsole and application JVM matches the JConsole JVM. 1.] # Configuration * Append the path of openjpa-fetch-statistics-version-SNAPSHOT.jar file to the classpath prior to lanuching the JVM. 2.] # Statistics Collecting and Monitoring * When this tool is configured, it will be active for all persistence units in the JVM. Statistics will be dumped via the openjpa.Runtime channel with the INFO level every 10 minutes, or when the JVM terminates. Any EAGER field that is logged has not been accessed by an application. 3.] # Configuration removal * Stop the JVM. * Remove openjpa-fetch-statistics-version-SNAPSHOT.jar from the classpath. Performance Consideration # If all goes well, at this point you should see a tab labeled DataCache-\[pu_name\]-\[n\] !screen.jpg|thumbnail,border=1! h3. Performance Consideration There will be a large performance impact when running this tooling. It is not supported, nor recommended for production use. This tool should not be used on a production machine. Full Content Fetching Statistics Open JPA Fetch Statistics Tool monitors persistent field access and determines which fields are never used. This tool can be used to help tune an application. Download The latest OpenJPA Tools JAR file can be download from the SNAPSHOT Repository or can be built from the source code in svn by using Maven 2.2.1 and Java SE 6. Usage This description assumes your application is running the on same machine as JConsole and application JVM matches the JConsole JVM. Configuration Append the path of openjpa-fetch-statistics-version-SNAPSHOT.jar file to the classpath prior to lanuching the JVM. Statistics Collecting and Monitoring When this tool is configured, it will be active for all persistence units in the JVM. Statistics will be dumped via the openjpa.Runtime channel with the INFO level every 10 minutes, or when the JVM terminates. Any EAGER field that is logged has not been accessed by an application. Configuration removal Stop the JVM. Remove openjpa-fetch-statistics-version-SNAPSHOT.jar from the classpath. If all goes well, at this point you should see a tab labeled DataCache-[pu_name]-[n] Unable to render embedded object: File (screen.jpg) not found. Performance Consideration There will be a large performance impact when running this tooling. It is not supported, nor recommended for production use. This tool should not be used on a production machine. Change Notification Preferences View Online | View Changes | Add Comment