Check manual page of j4p_performance.mem

j4p_performance.mem

Author: Mathias Kettner

License: GPL

Distribution: official part of Check_MK

Supported Agents: Linux

This checks uses the JSON HTTP service of j4p (from jmx4perl) to monitor the current memory usage of a Java application server like Tomcat or JBoss. You can define levels agains the total memory usage of the Java machine (heap + non heap).

In order for the check to work, you need to load the j4p.war into your application server. Furthermore you need the agent plugin j4p_performance in your Check_MK agent's plugins directory. If you do not use the default port 8080 for j4p - lets say 9090 - then you have to create a configuration file j4p.conf in the agents configuration directory (usually /etc/check_mk/j4p.conf) with the single line port = 9090.

Note: No jmx4perl is needed - neither on the target host nor on the monitoring server. No Perl is needed, either. The agent connects to the application server always via localhost.

Item

The instance name as configured in j4p.conf with the variable instance. If you do not specify an instance then the port number converted to a string is used.

Please note that the current implementation of the agent plugin supports only one instance per host.

Check parameters

Parameter	Type	Description
warning	int	The warning level for used memory in MB
critical	int	The critical level for used memory in MB

Performance data

Two variables: the heap memory usage and the non heap memory usage in MB.

Inventory

One check is created for each JMX instance sent by the agent. The agent currently supports only one instance, but that might be changed in future.

Configuration variables

Variable	Type	Description
j4p_mem_default_levels	int, int	Default levels for memory usage in MB. This is preset to (1000, 2000).

Examples

# Set default levels for heap memory to 500 MB / 800 MB
j4p_mem_default_levels = (500, 800)