Hi Mike, The problem was due to close(). A shutdown was calling close() which seems to cause lucene to perform a merge. For a busy very large index (with lots of deletes and updates), the merge process could take a very long time to complete (hours). Calling close(false) solved the problem as this appears to close the index without performing the merge. At least that is my understanding of things !
Clive ----- Original Message ----- From: Michael McCandless <luc...@mikemccandless.com> To: java-user@lucene.apache.org Cc: Sent: Tuesday, July 26, 2011 5:30 PM Subject: Re: Closing IndexWriter can be very slow on large indexes Which method (abort or close) do you see taking so much time? It's odd, because IW.abort should quickly stop any running BG merges. Can you get a dump of the thread stacks during this long abort/close and post that back? Can't answer if Lucene 3.x will improve this situation until we find the source of the slowness... Mike McCandless http://blog.mikemccandless.com On Tue, Jul 26, 2011 at 11:33 AM, Chris Bamford <chris.bamf...@talktalk.net> wrote: > Hi > > I think I must be doing something wrong, but not sure what. > > I have some long running indexing code which sometimes needs to be shutdown > in a hurry. To achieve this, I set a shutdown flag which causes it to break > from the loop and call first abort() and then close(). The problem is that > with a large index (say, 15Gb) in Lucene 2.3.2, it can take over an hour. > (Yes, I know I should be on a later version of Lucene, but that's another > issue - we are stuck with this for now!). > > The IW is opened in autoCommit mode and mergeFactor=10. > > During this closedown stage, the indexes are being constantly updated by > Lucene itself, making me suspect it could be merging. > > Firstly, can someone explain what it is doing under the covers that takes so > long? (And any action I can take to get around it) > > Second, if I were to rebuild the code with say, Lucene 3 and run it in > compatibility mode with the 2.3.2 indexes, would I have a richer set of tools > I could use to overcome the issue? > > Thanks, > > - Chris > --------------------------------------------------------------------- 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
