The document discusses performance testing of the Documentum xPlore search engine when deployed in a virtualized environment. It provides tips on ensuring sufficient hardware resources are allocated to virtual machines to avoid resource contention. It also describes pre-caching portions of the Lucene index in memory to improve response times when the index data is paged out of the operating system buffer cache. Testing showed pre-caching the stored fields, term dictionary, or positions data reduced average response times by up to 40% and lowered disk I/O per search result.