I'm running Lucene 2.3.1 with Java 1.5.0_14 on 64 bit linux. We have fairly large collections (~1gig collection files, ~1,000,000 documents). When I try to load test our application with 50 users, all doing simple searches via a web interface, we quickly get an OutOfMemory exception. When I do a jmap dump of the heap, this is what I see:
Size Count Class description ------------------------------------------------------- 195818576 4263822 char[] 190889608 13259 byte[] 172316640 4307916 java.lang.String 164813120 4120328 org.apache.lucene.index.TermInfo 131823104 4119472 org.apache.lucene.index.Term 37729184 604 org.apache.lucene.index.TermInfo[] 37729184 604 org.apache.lucene.index.Term[] So 4 of the top 7 memory consumers are Term related. We have 2 gig of RAM available on the system but we get OOM errors no matter the java heap settings. Has anyone seen this issue and know how to solve it? We do use separate MultiSearcher instances for each search. (We actually have 2 collections that we search via a MultiSearcher.) We tried using a singleton searcher instance but our collections are constantly being updated and the singleton searcher only gives you results since the searcher was opened. Creating new searcher objects at search time gives you up to the minute search results. I've seen some postings referring to an Index Divisor setting which could reduce the Terms in memory, but I have not seen how to set this value for Lucene. Any help would be greatly appreciated. Rich