Hi, I'm pretty new to Lucene, so please bear with me if this has been covered before.
The wiki suggests sharing a single IndexSearcher between threads for best performance (http://wiki.apache.org/lucene-java/ImproveSearchingSpeed). I've tested running the same set of queries with: multiple threads sharing the same searcher, with a separate searcher for each thread, both shared/private with a RAMDirectory in-memory index, and (just for fun) in multiple JVMs running concurrently (the results are in milliseconds to complete the whole job): threads multi-jvm shared per-thread ram-shared ram-thread 1 72997 70883 72573 60308 60012 2 33147 48762 35973 25498 25734 4 16229 46828 21267 13127 27164 6 13088 47240 14028 9858 29917 8 9775 47020 10983 8948 10440 10 8721 50132 11334 9587 11355 12 7290 49002 11798 9832 16 9365 47099 12338 11296 The shared searcher indeed behaves better with a ram-based index, but what's going on with the disk-based one? It's basically not scaling beyond two threads. Am I just doing something completely wrong here? The test consists of about 1,500 Boolean OR queries with 1-10 PhraseQueries each, with 1-20 Terms per PhraseQuery. I'm using a HitCollector to count the hits, so I'm not retrieving any results. The index is about 5GB and 20 million documents. This is running on a 8 x quad-core Opteron machine with plenty of RAM to spare. Any idea why I would see this behaviour? Thanks, Dmitri --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
