Hi Emmanuel, Because there are some synchronized methods, like the one that checks whether a doc is deleted, that get called during search. If you have a pile of threads (op. p. mentioned 100 threads) there could be contention around those methods.
Otis -- Sematext -- http://sematext.com/ -- Lucene - Solr - Nutch ----- Original Message ---- > From: Emmanuel Bernard <[EMAIL PROTECTED]> > To: java-user@lucene.apache.org > Sent: Friday, May 23, 2008 6:41:36 PM > Subject: Re: Improving search performance > > Hi > Hibernate Search does not pool the Searcher but pools the underlying > IndexReader(s). From what i've seen, a Searcher is stateless and all > the state is kept in the Readers. so this essentially is equivalent to > reusing the searcher. > > Out of curiosity why is a pool of Searcher more efficient? > > Emmanuel > > On May 22, 2008, at 13:22, Otis Gospodnetic wrote: > > > Some quick feedback. Those are all very expensive queries > > (wildcards and ranges). The first thing I'd do is try without > > Hibernate Search (to make sure HS is not the bottleneck). 100 > > threads is a lot, I'm guessing you are reusing your searcher, which > > is good, but you will actually improve performance a bit if you work > > with a small pool of searchers instead of a single searcher. > > > > Otis > > -- > > Sematext -- http://sematext.com/ -- Lucene - Solr - Nutch > > > > > > ----- Original Message ---- > >> From: Rakesh Shete > >> To: [EMAIL PROTECTED]; java-user@lucene.apache.org > >> Sent: Thursday, May 22, 2008 1:16:13 PM > >> Subject: Improving search performance > >> > >> > >> Hi all, > >> > >> I have index of size 85MB. My query looks as follows: > >> > >> +(t:boss* d:boss* dd:boss* tg:boss*) +st:act +ntid:0 +cid:1 +dr: > >> [20080410 TO > >> 20081010] +rT:[002 TO 005] > >> > >> All the fields used in the query are stored in the indexes (Indexed > >> & Stored) > >> > >> The query response time for me is around 30 seconds when running > >> mutliple > >> simultanoeous threads (~100). The no. of matches is ~30k but I > >> retrieve only the > >> top 100 results. I am using Hibernate Search which is a wrapper > >> around Lucene. I > >> retrieve the "id" filed from the index which is also indexex and > >> stored. > >> > >> What is the approach that I should take for improving the > >> performance? > >> > >> Will just indexing the values without storing them work (Index & > >> UnStored)? > >> > >> My machine configuration is: > >> P4 2.66GHz 1.99 GB RAM > >> > >> The code for searching runs in JBoss application server which has a > >> maximum heap > >> size of 1024MB. When these 100 threads are running in the > >> application server the > >> CPU utilization is 100% and JBoss consumes all of the heap size. > >> > >> Any pointers on index optimization would be really appreciated. > >> > >> --Regards, > >> Rakesh Shete > >> > >> _________________________________________________________________ > >> No Harvard, No Oxford. We are here. Find out !! > >> http://ss1.richmedia.in/recurl.asp?pid=500 > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
