7 Setting Server Parameters to Support Enterprise Data Quality
This chapter contains the following topics:
How to Set the Server Parameters
This section describes how to set the recommended server parameters for WebLogic Server and Tomcat domains. Follow the guidelines that are appropriate for your EDQ installation.
How to Set Server Parameters in a WebLogic Server Domain
When you start a Managed Server in a WebLogic Server domain, the startup passes a set of configuration parameters to initialize a Java Virtual Machine (JVM). These parameters include, but are not limited to, the server's JVM settings and the path to the server configuration directories.
The method of setting the required server configuration parameters for EDQ varies, depending on the method that you use to start the Managed Servers. The following points explain the differences:
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When starting an EDQ Managed Server from the WebLogic Server Remote Console, the configuration settings for the Managed Server are pre-defined as server startup arguments, because they were set by the domain Configuration Wizard (see Creating the WebLogic Server EDQ Domain). When starting the server, these arguments are applied by default, but you can change them to the recommended settings described in Recommended Parameter Values.
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When starting an EDQ Managed Server by using a startup script, the server startup arguments that are defined in the WebLogic Server Remote Console are ignored. However, when the domain Configuration Wizard was run, it created an
edq_server1
Managed Server that contains default JVM settings. These settings are stored in thesetStartupEnv.cmd
(Windows) orsetStartupEnv.sh
(Linux) script. You can edit this script to add or change the name of the Managed Server and to apply the recommended JVM settings described in Recommended Parameter Values.
Recommended Parameter Values
This section describes the recommended server parameter settings.
Setting JVM Parameters
You must set the following parameters for the Java Virtual Machine (JVM) that runs the EDQ environment. Most of these parameters apply to the HotSpot JVM, which is the central JVM of the Java Development Kit (JVM) from Oracle. This is the preferred JVM because it yields the best performance for EDQ.
-
Maximum heap memory,
-Xmx,
should normally be set to approximately 50% of available physical memory on the host server. For example, on a server with 32GB of RAM, start by setting it to 16GB with-Xmx16384m
. Depending on the relative usage of memory between the JVM and native processing, you may need to be adjust this setting. This parameter is common to most JVMs. -
Reserved Code Cache size should be set to 128m,
-XX:ReservedCodeCacheSize=128m
. However, for systems running CDS or OWS, where there are a lot of scripts, it is advisable to set the Reserved Code Cache size to 512m. This parameter is specific to HotSpot JVM.
Setting Other Parameters
The following additional parameter setting is recommended.
-
Headless mode should always be set to true on UNIX systems,
-Djava.awt.headless=true
. This parameter is specific to the Java Abstract Window Toolkit (AWT) library. Setting this is recommended because some of the graphic drawing routines (such as around graphs) will attempt to connect to the display device on a client to size fonts and other attributes. If the machine does not have a display device, this may interfere with operation. Theheadless=true
setting directs the graphics library to operate without connecting to a display.