Are you opening your IndexReader with readOnly=true? If not, you're likely hitting contention on the "isDeleted" method.
When you run with a "normal" directory, either on a traditional hard drive or SSD device, do you use NIOFSDirectory? That removes contention, but, it only works on non-Windows platform due to a long-standing bug in Sun's JRE. Likely the OS is caching stuff in RAM, anyway, so you don't see much improvement when you explicitly load into a RAMDir. Mike On Fri, Mar 27, 2009 at 7:07 AM, Paul Taylor <paul_t...@fastmail.fm> wrote: > Hi > > I am trying to run the performance tests against lucene, and am suprised > about the results. > > I have a test that creates a queue of queries, and a number of threads. The > threads run concurrently getting the next query available, peforming a query > on the index and taking the top hits. The index is 2GB in size, and was > originally created froma database table of about 7 millions rows. > > I ran the test a number of times with 30 threads, and max memory of 3500mb I > was processing 10,000 records in about 43 seconds ( 233 queries/second) , > the index was stored on a solid state drive running on a MacBook Pro (2.66 > Ghz Intel Core 2 Duo, 4GB DDR). I dont really have a view on whether this is > a good result or not but I was keen to try a few other things to see if I > could improve performance further, but all my efforts have had minimal > effect. > > I tried creating a RAMDirectory based on the file index, once the index had > been created (4 min 20 seconds) it again took > I copied the index to a slower external convention hard drive and it still > took 43 seconds. > > Reducing/increasing the memory allocated and the number of threads had > minimal impact. > > The main thing Im suprised about is I was expecting a massive difference in > holding the index in memory instead on disk > > thanks Paul > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org > > --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
