Generally the 1.5GB memory maximum limit of the 32-bit JRE is sufficient for Workflow, but under heavy usage this may not be enough. This document details how to configure Workflow's Tomcat to use a 64-bit JRE to allow additional memory to be designated for use by Workflow.
The following will only work in a 64-bit Environment and should only be attempted on systems with more than 4 gigabytes (GB) of available memory.
@NX_JAVA_OPTIONS_CAWF=-Djava.net.preferIPv4Stack=false -Xms64M [email protected]_JRE_INSTALL_DIR_CAWF=C:/Progra~1/Java/jre6where the -Xmx2048M is the maximum memory Java will utilize, and the JRE_INSTALL_DIR is the location where the 64-bit JRE has been installed. This does not have to be an exact value - for instance 4096 MM for 4 GB; you can specify 5000M as long as the resources are available.
The new memory setting should be visible in the stdlog on the startup_tomcat line:
startup_tomcat: C:/Progra~1/Java/jre6... -Djava.net.preferIPv4Stack=false -Xrs64M -Xmx2G...
Currently there is no upper limit to the amount of memory that can be specified for the 64-bit JRE. If you have 16 GB of RAM on your Workflow Server, it is conceivable to dedicate 10 GB to Tomcat for Workflow. This however is an extreme example and for most implementations dedicating an amount between 4 GB and 6 GB should be more than enough.