By default, the eviction policy is disabled and we need to configure DataRegionConfiguration to turn it on. When the eviction policy is pre-configured, Ignite starts purging the pages as the memory consumption of the data region gets to 90% of the allocated memory of the data region. During eviction, Ignite applies the user-configured eviction algorithm and finds the pages to purge. It can completely remove the entries from the page. However, it cannot purge the entire page when an entry is locked and actively participating in a transaction. In cases like this, Ignite removes all other entries from the page and frees up some memory.

The off-heap eviction policy supports two least recently used (LRU) algorithms for selecting pages.