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10.1 Tuning Memory

This section describes how to adjust the resources available to your MySQL Enterprise Service Manager installation.

Tuning Tomcat

If you experience MySQL Enterprise Service Manager performance issues, increasing the amount of RAM available to the JVM installed with Tomcat can resolve those issues. The JVM memory settings are defined by the JAVA_OPTS line of the setenv file which sets the environment variables for Tomcat.

Table 10.1 Apache Tomcat Environment File Location (default)

Operating System Path

Microsoft Windows

C:\Program Files\MySQL\Enterprise\Monitor\apache-tomcat\bin\setenv.bat

Linux / Unix




The following setenv variables are defined by the installation type:

Table 10.2 Installation Parameters

Parameter Small Medium Large

Tomcat Heap Size




Tomcat MaxPermSize




  • --JvmMs (Windows)/-Xms (all other platforms): sets the minimum size of the Tomcat JVM heap.

  • --JvmMx(Windows)/-Xmx (all other platforms): sets the maximum size of the Tomcat JVM heap.

    The minimum and maximum heap size are set to the same value to have all the available memory set for the Tomcat JVM's sole use from startup.

  • MaxPermSize: defines the maximum size of the pool containing the data used by Tomcat's JVM.


    MaxPermSize is not supported in Java 8. This parameter is not present in new installations of MySQL Enterprise Service Manager, but is not removed by the upgrade process. As a result, a log message is generated explaining the deprecation of the parameter.

This can be adjusted depending on the size of your installation, and the free memory on the host that MySQL Enterprise Service Manager is installed upon. For example, if you have installed MySQL Enterprise Service Manager on a well-resourced server with a 64-bit operating system, 64GB of RAM, and are monitoring more than 100 agents, increasing the heap size to 5 or 6GB may be necessary. This depends on the MySQL server load, and amount of data collected by the agents.


If you change these settings, you must restart MySQL Enterprise Service Manager.

The following are examples of medium-sized, default settings, as defined by the medium installation choice:

UNIX, Linux, and Mac

JAVA_OPTS="-Xmx768M -Xms768M -XX:+HeapDumpOnOutOfMemoryError 
  -XX:+UseParallelOldGC -XX:MaxPermSize=512M"

Microsoft Windows

set JAVA_OPTS=--JvmMs 768 --JvmMx 768 ++JvmOptions="-XX:+UseParallelOldGC" 

If MySQL Enterprise Service Manager is insufficiently resourced, the monitoring agents are also affected. If the agents are unable to communicate with MySQL Enterprise Service Manager, their performance also degrades.

Tuning InnoDB Memory

MySQL Enterprise Monitor repository uses the InnoDB storage engine. The installation process sets a default value for InnoDB based on the installation size. Tuning the InnoDB Buffer Pool can have a significant impact on performance, for both interaction with the Web UI, and overall resource requirements on the host.

The configuration file for the repository can be found in the following locations:

Table 10.3 MySQL Enterprise Service Manager repository configuration file location (default)

Operating System Path

Microsoft Windows

C:\Program Files\MySQL\Enterprise\Monitor\mysql\my.ini

Linux / Unix




It is possible to increase the value of the innodb_buffer_pool_size variable to as high as 80% of the physical memory available on the host machine. It is not recommended to raise it higher.