Stardust Portal Performance Tuning

This chapter describes the following options to tune performance for the Stardust Process Portal.

Caching Process Instances

Stardust provides a mechanism to cache process instances for a better performance in the Stardust Portal. By default, the cache is disabled. To enable this functionality, set the following properties, residing in your client-side carnot.properties:

Carnot.Client.Caching.ProcessInstanceContext.Enabled = true
Carnot.Client.Caching.ProcessInstanceContext.CacheSize = 100
Carnot.Client.Caching.ProcessInstanceContext.CacheTTL = 120

Please note that, as this is a session level client side cache, each user will have its own copy.

Disabling Caching Information on XPathMaps

Caching information about XPathMaps can produce a massive log output which causes very large log files. You can switch off the logging of XPathMaps by setting the client side property Carnot.Client.Caching.ClientXPathMap.Enabled to false in your carnot.properties file:

Carnot.Client.Caching.ClientXPathMap.Enabled=false

The default value is true.

Resolving Performance Problems caused by Refresh Period

Performance problems might occur due to Facelets version 1.1.14, where any facelet template or composition component contained within a jar is continuously refreshed, even if a file has not been updated. This occurs when the facelets.REFRESH_PERIOD context parameter is set to a value greater than -1.

Via the following configuration changes in your web.xml file, this can be avoided and the performance of the Stardust portal can be enhanced:

  1. Set the facelets.REFRESH_PERIOD context parameter to -1 to turn off the facelets timestamp checking: 
    <context-param> 
        <param-name>facelets.REFRESH_PERIOD 
        </param-name> 
        <param-value>-1</param-value> 
</context-param>
  2. Set the init param mode to the value production. Thus the content will be cached internally and not resolved against JARs more than once. 
    <filter>
    <filter-name>portalPluginContentFilter</filter-name>
    <filter-class>org.eclipse.stardust.ui.web.plugin.support.PortalPluginContentFilter</filter-class>
    <init-param>
        <param-name>mode</param-name>
        <param-value>production</param-value>
    </init-param>
</filter>