Database Reference
In-Depth Information
Accessing MBeans using JConsole
JConsole is a built-in utility in JDK 5+. You can access it from
$JAVA_HOME/bin/
jconsole
. It is a JVM monitoring tool and allows you to access MBeans in the Java ap-
plication to which JConsole is connected. It allows you to monitor the CPU, memory,
thread pools, heap information, and other important JVM-related things.
To peek into the insides of Cassandra, launch JConsole. The GUI shows two options to
connect to—
Local Process
and
Remote Process
. If you are running JConsole on the same
machine as Cassandra, you will see the option to connect to Cassandra in the drop-down
under the
Local Process
radio button. However, it is not recommended to run JConsole on
the same machine as Cassandra. This is because JConsole takes a large amount of system
resources and can hamper Cassandra's performance. Thus, unless you just want to test Cas-
sandra on your local machine, it may not be a good idea to have Cassandra and JConsole
running on the same machine.
The
Overview
tab of JConsole is shown in the following screenshot:
To connect to a remote machine, you need to select the
Remote process
radio button and
fill in the URL of the Cassandra node. The format is as follows:
# CASSANDRAHOST is address of remote Cassandra node
service:jmx:rmi:///jndi/rmi://CASSANDRAHOST:7199/jmxrmi
If you have a firewall or port blocking the Cassandra node, you may face some issues in
connection.
