3.3. Using Eviction
In Red Hat JBoss Data Grid, eviction is disabled by default. If an empty <
eviction /> element is used to enable eviction without any strategy or maximum entries settings, the following default values are automatically implemented:
- Strategy: If no eviction strategy is specified,
EvictionStrategy.NONEis assumed as a default. - max-entries/maxEntries: If no value is specified, the
max-entries/maxEntries value is set to-1, which allows unlimited entries.
3.3.1. Initialize Eviction
To initialize eviction, set the eviction element's
max-entries attributes value to a number greater than zero. Adjust the value set for max-entries to discover the optimal value for your configuration. It is important to remember that if too large a value is set for max-entries, Red Hat JBoss Data Grid runs out of memory.
The following procedure outlines the steps to initialize eviction in JBoss Data Grid:
Procedure 3.1. Initialize Eviction
Add the Eviction Tag
Add the <eviction> tag to your project's <cache> tags as follows:<eviction />
Set the Eviction Strategy
Set thestrategyvalue to set the eviction strategy employed. Possible values areLRU,UNORDEREDandLIRS(orNONEif no eviction is required). The following is an example of this step:<eviction strategy="LRU" />
Set the Maximum Entries
Set the maximum number of entries allowed in memory. The default value is-1for unlimited entries.- In Library mode, set the
maxEntriesparameter as follows:<eviction strategy="LRU" maxEntries="200" />
- In Remote Client Server mode, set the
max-entriesas follows:<eviction strategy="LRU" max-entries="200" />
Result
Eviction is configured for the target cache.
