Hi, you should not use too much heap space for the Java VM because Lucene relies heavily on the file system cache. If your machine has say 32 Gigs of RAM don't use more than 1/4 (8 DB) as heap for the Java application. Ideally only use so much heap + some overhead, that you get no OOMs (this depends on your index size and application). Lucene generally uses only few heap space unless very huge field caches are used.
For the concurrency problem, as Mike already said, try using MMapDirectory (which is supported on Lucene 2.4, too - but not yet so efficient and does not support unmapping) instead of FSDirectory. For more information, see http://blog.thetaphi.de/2012/07/use-lucenes-mmapdirectory-on-64bit.html RandomAccessFile (which is used by FSDirectory) is not behaving well in multi-threaded environments, because the underlying file descriptor can only be used single-threaded. Uwe ----- Uwe Schindler H.-H.-Meier-Allee 63, D-28213 Bremen http://www.thetaphi.de eMail: u...@thetaphi.de > -----Original Message----- > From: RameshIyerV [mailto:rameshiy...@hotmail.com] > Sent: Monday, July 22, 2013 11:15 AM > To: dev@lucene.apache.org > Subject: Re: Contentions observed in lucene execution > > Thanks Mike, > > This is running on Hotspots VM (on unix) & the JVM has 24 GB of max heap. > > Moving to Lucene 4.X is not an easy option because for us Lucene has > shipped as part of the Sterling 9.0 product & if we upgrade part of the > product we would have to give away support. > > One of my coworkers had the same doubt (that we are running out of heap - > although I am not so sure because the warnings appear in the logs after 100's > of stuck threads) and so we plan to bump up the heap to a max of 34 and > then watch closely. I'll post if that does not work, thanks for taking a look. > > - Ramesh. > > > > -- > View this message in context: > http://lucene.472066.n3.nabble.com/Contentions-observed-in-lucene- > execution-tp4078796p4079410.html > Sent from the Lucene - Java Developer mailing list archive at Nabble.com. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional > commands, e-mail: dev-h...@lucene.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
