I don't think a toplevel BS2 is able to use BS as sub-scorers? BS2 needs to do doc-at-once, for all sub-scorers, but BS can't do that. I think?
Mike On Wed, Jul 15, 2009 at 12:10 PM, Paul Elschot<paul.elsc...@xs4all.nl> wrote: > On Wednesday 15 July 2009 17:16:23 Michael McCandless wrote: >> So now I'm confused. Since your query has required (+) clauses, the >> setAllowDocsOutOfOrder should have no effect, on either 2.4 or trunk. > > Probably the top level BQ is using BS2 because of the required clauses, > but the nested BQ's are using BS because the docs are allowed out of order. > > In that case BS2 will use skipTo() on BS, and the BS.skipTo() implementation > could well be the culprit for performance. A long time ago BS.skipTo() used to > throw an unsupported operation exception, but that does not seem to > be happening. > > Eks, could you try a toString() on the top level scorer for one of the > affected > queries to see whether it shows BS2 on top level and BS for the inner scorers? > > Regards, > Paul Elschot > > >> >> BooleanQuery only uses BooleanScorer when there are no required terms, >> and allowDocsOutOfOrder is true. So I can't explain why you see this >> setting changing anything on this query... >> >> Mike >> >> On Tue, Jul 14, 2009 at 7:04 PM, eks dev<eks...@yahoo.co.uk> wrote: >> > >> > I do not know exactly why, but >> > when I BooleanQuery.setAllowDocsOutOfOrder(true); I have the problem, but >> > with setAllowDocsOutOfOrder(false); no problems whatsoever >> > >> > not really scientific method to find such bug, but does the job and makes >> > me happy. >> > >> > Empirical, "deprecated methods are not to be taken as thoroughly tested, >> > as they have short life expectancy" >> > >> > >> > >> > >> > >> > ----- Original Message ---- >> >> From: eks dev <eks...@yahoo.co.uk> >> >> To: java-user@lucene.apache.org >> >> Sent: Wednesday, 15 July, 2009 0:24:43 >> >> Subject: Re: speed of BooleanQueries on 2.9 >> >> >> >> >> >> Mike, we are definitely hitting something with this one! >> >> >> >> we had report from our QA chaps that our servers got stuck (limit is on >> >> 180 >> >> Seconds Request)... We are on average 14 Requsts per second.... has >> >> nothing to >> >> do with gc() as >> >> we can repeat it with freshly restarted searcher. >> >> >> >> - it happens on a less than 0.1% of queries, not much of a pattern, >> >> repeatable >> >> on our index... >> >> it is always combination of two expanded tokens (we use >> >> minimumNooShouldMatch)... >> >> >> >> (+(t1 [up to 40 expansions]) +(t2 [up to 40 expansions of t2])) >> >> all tokens are with set boost, and minNumShouldMatch is set to two >> >> >> >> I cannot provide self-contained test, nor index (contains sensitive data >> >> and is >> >> rather big, ~5G) >> >> >> >> I can repeat this test on t1 and t2 with 40 expansions each. even if I >> >> take the >> >> most frequent tokens in collection it runs well under one second...but >> >> these two >> >> particular tokens with their "expansions" are making it run forever... >> >> >> >> and yes, if I run t1 plus expansions only, it runs super fast, the same >> >> for t2 >> >> >> >> java 1.4U14, tried wit 1.6U6, no changes... >> >> >> >> will report if I dig something out >> >> >> >> partial stack trace while "stuck", cpu is on max: >> >> >> >> org.apache.lucene.search.TopScoreDocCollector$OutOfOrderTopScoreDocCollector.collect(Unknown >> >> Source) >> >> org.apache.lucene.search.BooleanScorer.score(Unknown Source) >> >> org.apache.lucene.search.BooleanScorer.score(Unknown Source) >> >> org.apache.lucene.search.IndexSearcher.search(Unknown Source) >> >> org.apache.lucene.search.IndexSearcher.search(Unknown Source) >> >> org.apache.lucene.search.Searcher.search(Unknown Source) >> >> >> >> >> >> >> >> >> >> >> >> ----- Original Message ---- >> >> > From: eks dev >> >> > To: java-user@lucene.apache.org >> >> > Sent: Monday, 13 July, 2009 13:28:45 >> >> > Subject: Re: speed of BooleanQueries on 2.9 >> >> > >> >> > Hi Mike, >> >> > >> >> > getMaxNumOfCandidates() in test was 200, Index is optimised and >> >> > read-only >> >> > >> >> > We found (due to an error in our warm-up code, funny) that only this >> >> > Query >> >> runs >> >> > slower on 2.9. >> >> > >> >> > A hint where to look could be that this Query cointains two, the most >> >> > frequent >> >> >> >> > tokens in two particular fields >> >> > NAME:hans and ZIPS:berlin (index has ca 80Mio very short documents, 3Mio >> >> unique >> >> > terms) >> >> > >> >> > But all of this *could be just wrong measurement*, I just could not >> >> > spend more >> >> >> >> > time to get to the bottom of this. We moved forward as we got overall >> >> > better >> >> > average performance (sweet 10% in average) on much bigger real query >> >> > log from >> >> > our regression test. >> >> > >> >> > Anyhow I just wanted to throw it out, maybe it triggers some synapses >> >> > :) If >> >> > false alarm, sorry. >> >> > >> >> > >> >> > >> >> > >> >> > >> >> > ----- Original Message ---- >> >> > > From: Michael McCandless >> >> > > To: java-user@lucene.apache.org >> >> > > Sent: Monday, 13 July, 2009 11:50:48 >> >> > > Subject: Re: speed of BooleanQueries on 2.9 >> >> > > >> >> > > This is not expected; 2.9 has had a number of changes that ought to >> >> > > reduce CPU cost of searching. If this holds up we definitely need to >> >> > > get to the root cause. >> >> > > >> >> > > Did your test exclude the warmup query for both 2.4.1 & 2.9? How many >> >> > > segments in the index? What is the actual value of >> >> > > getMaxNumOfCandidates()? If you simplify the query down (eg just do >> >> > > the NAME clause or the ZIPSS clause, alone) are those also 4X slower? >> >> > > >> >> > > Mike >> >> > > >> >> > > On Sun, Jul 12, 2009 at 12:53 PM, eks devwrote: >> >> > > > >> >> > > > Is it possible that the same BooleanQuery on 2.9 runs significantly >> >> > > > slower >> >> >> >> > > than on 2.4? >> >> > > > >> >> > > > we have some strange effects where the following query runs approx >> >> 4(ouch!) >> >> > > times slower on 2.9, test done by 1000 times executing the same >> >> > > Query... >> >> But! >> >> > if >> >> > > I run test from some real Query log with mixed Queries, I get almost >> >> > > the >> >> same >> >> > > results (?!), even slightly faster on 2.9 !? >> >> > > > >> >> > > > >> >> > > > Query: >> >> > > > +((NAME:hans NAME:hahns^0.23232001 NAME:hams^0.27648002 >> >> > > > NAME:hamz^0.25392 >> >> > > NAME:hanas^0.18722998 NAME:hanbs^0.18722998 NAME:hanfs^0.18722998 >> >> > > NAME:hangs^0.18722998 NAME:hanhs^0.24030754 NAME:hanis^0.18722998 >> >> > > NAME:hanjs^0.18722998 NAME:hanks^0.18722998 NAME:hanms^0.18722998 >> >> > > NAME:hanos^0.18722998 NAME:hanrs^0.18722998 NAME:hansb^0.20172001 >> >> > > NAME:hansd^0.20172001 NAME:hansf^0.20172001 NAME:hansg^0.20172001 >> >> > > NAME:hansi^0.20172001 NAME:hansj^0.20172001 NAME:hansk^0.20172001 >> >> > > NAME:hansl^0.20172001 NAME:hansn^0.20172001 NAME:hanso^0.20172001 >> >> > > NAME:hansp^0.20172001 NAME:hanst^0.20172001 NAME:hansu^0.20172001 >> >> > > NAME:hansw^0.20172001 NAME:hansy^0.20172001 NAME:hansz^0.20172001 >> >> > > NAME:hants^0.18722998 NAME:hanus^0.18722998 NAME:hanws^0.18722998 >> >> > > NAME:hehns^0.20172001 NAME:hens^0.2736075 NAME:hins^0.24843 >> >> NAME:hons^0.24843 >> >> > > NAME:huhns^0.1801875 NAME:huns^0.24843)^2.0) >> >> > > > +(((ZIPS:berlin ZIPS:barlin^0.28227 ZIPS:berien^0.25947002 >> >> > > ZIPS:berling^0.23232001 ZIPS:perlin^0.26133335))^1.2) >> >> > > > >> >> > > > The question is just to get some hints where I should look... >> >> > > > >> >> > > > Both fealds are without norms, omitTf(true) , RAMDirectory, using >> >> > > > TopDocs top = ixSearcher.search(q, null, getMaxNumOfCandidates()); >> >> > > > and BooleanQuery.setAllowDocsOutOfOrder(true); >> >> > > > >> >> > > > maybe we made some mistakes on measuring, but we did simple timing >> >> > > > here on >> >> >> >> > > search() method... strange. I would bet it is something we did, but I >> >> > > cannot >> >> >> >> > see >> >> > > where ... >> >> > > > >> >> > > > >> >> > > > >> >> > > > >> >> > > > >> >> > > > --------------------------------------------------------------------- >> >> > > > 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 >> >> >> >> >> >> >> >> >> >> >> >> --------------------------------------------------------------------- >> >> 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 >> > >> > >> >> --------------------------------------------------------------------- >> 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
