Chapter 9. Red Hat JBoss Data Grid as Lucene Directory

Red Hat JBoss Data Grid can be used as a shared, in-memory index (Infinispan Directory) for Hibernate Search queries on a relational database. By default, Hibernate Search uses a local filesystem to store the Lucene indexes but optionally it can be configured to use JBoss Data Grid as a storage to achieve real-time replication across multiple server nodes.

In the Infinispan Directory, the index is stored in memory and shared across multiple nodes. The Infinispan Directory acts as a single directory distributed across all participating nodes. An index update on one node updates the index on all the nodes. Index can be searched immediately after the node update across the cluster. The default Hibernate Search configuration replicates the data defining the index across all the nodes.

Data distribution for large indexes may be enabled to consume less memory; however, this will come at a cost of locality resulting in query operations less efficient. The indexed data can also be offloaded to a CacheStore configured on each node or configure a single centralized CacheStore shared by each node.