In OpenWGA admin client enable the "expert mode" by the checkbox to the top-right, then navigate to "Configuration > Advanced Configuration", there to Tab "Lucene engine" to see the advanced configuration options for the Lucene engine on your installation.
The settings in detail:
- The Path to lucene index determines where the index files are stored. This typically is below the OpenWGA data directory. As the lucene index may grow very large with much content and you always should have twice the size of the lucene index free on the drive that stores it to allow optimization you may want to move this location somewhere else. Note that the index will be completely rebuilt at the new location.
- The option Regularly optimize index once a day controls the scheduled index optimization, which consolidates the index files to take up less drive space and perform better.If this option is enabled you will find a job "Optimize lucene index" on the jobs list of your server which performs this task at 0:30 each day. If for some reason this not ok for your installation you can disable it here and schedule a manual job yourself which runs the task "Optimize lucene index".
- The Number of max. boolean Clauses determines what compexity a boolean query may have to be executed. Too complex queries may influence the servers health negatively and make it unresponsive and are therefor to be prohibited. However: Certain special type of queries like "range queries" (querying for a range of values) may be more complex in the backend than they appear and you may run into a lucene error stating that the "max boolean clause count has been reached" depending on your amount of data. Use this field to adjust the threshold to your exact needs so you avoid this error.
- The Max. documents per database session controls how many documents the Lucene indexer may load before it reopens the session to clear caches. A higher value is slightly more performant but may mean that the indexer takes up more memory. A lower value down to 1 can be necessary if you have very much data per document in your content stores and you need to keep the indexer from threatening your servers memory health because of this.
- The Indexing interval in ms determines in milliseconds how often the indexer runs. A lower value means that content changes are indexed more instantly but will also increase CPU traffic.