jmx-extraction

All-command-line-configured utility for grabbing the values of named MBean properties to stdout

By default does not show status to stdout - this is logged to /tmp/jmx-extractor.log

$ tail -F /tmp/jmx-extractor.log

Design Summary

• invoked using cron or sensu's scheduler
  • non-memory resident during inactive times - exits when complete or timed out
• one invocation per MBean per JMX connection
  • any number of properties of that MBean
• prints to stdout by default
  • extensible to make other renderers (e.g. to a file)
• all config is visible on command line for ease of logging and modularity
  • Host logging details: tier, app, utility, hostname
  • JMX service details: host, port, jndi, user/pass
  • MBean metric details: domain, matched string in key, metrics to log
• all error or logging messages do NOT appear on stdout

Usage

Compile

  $ mvn -U clean package

in development

Print all values of all attributes on all MBeans:

  $ java -jar target/jmx-extraction-1.0-SNAPSHOT.jar     \
    -H localhost -P 18063 -J /jmxrmi                     \

Accessing only MBeans with "Pooled" in their canonical names, printing only the values of the named attributes:

  $ java -jar target/jmx-extraction-1.0-SNAPSHOT.jar     \
    -H localhost -P 18063 -J /jmxrmi                     \
    -k Pooled                                            \
    -c "numConnections,numIdleConnections,numBusyConnections,threadPoolNumActiveThreads,threadPoolNumIdleThreads"

in production

Change the route to the jar file, and use the same arguments

Usage listing

usage: java -jar jmx-extraction.jar
  -H,--jmxHost <arg>         the host serving the JMX interface
  -J,--jmxJndi <arg>         the JNDI name of the JMX interface
  -P,--jmxPort <arg>         the port for the JMX interface
  -U,--jmxUser <arg>         OPTIONAL username for a secured JMX interface
  -W,--jmxPassword <arg>     OPTIONAL password for a secured JMX interface
  -k,--keyMatch <arg>        OPTIONAL substring used to find the MBean
  -c,--csvAttributes <arg>   OPTIONAL comma-separated list of attributes to monitor

Parameter description

Sample output

One metric per line:

 (com.mchange.v2.c3p0:identityToken=2sodxj945wawqglpchmh|2d7b8b45,\
    name=FooC3P0PooledDataSource,type=PooledDataSource) \
    name=numIdleConnections value=0

JMX connection parameters

• -H or --jmxHost
  • the JMX host name
  • example: localhost
• -P or --jmxPort
  • the JMX port which is listening for requests
  • example: 18063
• -J or --jmxJndi
  • the JMX host name
  • example: /jmxrmi
• -U or --jmxUser
  • optional
  • the JMX user name for a secured connection
  • example: admin
• -W or --jmxPassword
  • optional
  • the JMX password for a secured connection
  • example: start123

MBean specification parameters

• -k or --keyMatch
  • a substring appearing in a portion of key/value, specifying an MBean to search
  • example: Billy (see above C3P0 example)
  • if omitted, will search for all beans and all properties
• -c or --csvAttributes
  • the comma-separated list of attributes we want from this MBean
  • example: "numConnections,numIdleConnections,numBusyConnections,threadPoolNumActiveThreads,threadPoolNumIdleThreads"

Development Notes

Compiling

All done in Maven

 $ mvn -U clean package

Appendix: Expose the JMX on the service

For example, how does jetty expose its MBeans so this utility can read from them?

Add these flags to the java

  -Dcom.sun.management.jmxremote.port=9999 \
  -Dcom.sun.management.jmxremote \
  -Dcom.sun.management.jmxremote.local.only=false

if running locally, disable the security

  -Dcom.sun.management.jmxremote.authenticate=false \
  -Dcom.sun.management.jmxremote.ssl=false

More reading:

• how to activate jmx on my jvm for access with jconsole

Labelling your C3P0

To make it easier to distinguish c3p0 instances, you can name each pool.

In src/main/resources/c3p0.properties :

• set the property "c3p0.dataSourceName" to a name specific to this application's data source
• "com.mchange.v2.c3p0.management.RegistryName" configures name of the entire c3p0 registry

Example:

 c3p0.dataSourceName=FooC3P0PooledDataSource
 com.mchange.v2.c3p0.management.RegistryName=FooC3P0PooledDataSourceRegistry