Many times, the queries that are run on search are repetitive in nature. In such cases, the presence of a cache brings down the average response time for search results. Apache Solr provides a caching mechanism on top of the index data. This cache, unlike a normal cache, does not carry any expiry (persistent cache). It is associated with IndexWriter. The following are the three different types of cache supported by Solr:
The following are the common parameters for the cache in solrconfig.xml: