It looks like you are using int join keys so you may want to check out SOLR-4787, specifically the hjoin and bjoin.
These perform well when you have a large number of results from the fromIndex. If you have a small number of results in the fromIndex the standard join will be faster. On Wed, Sep 25, 2013 at 3:39 PM, Peter Keegan <peterlkee...@gmail.com>wrote: > I forgot to mention - this is Solr 4.3 > > Peter > > > > On Wed, Sep 25, 2013 at 3:38 PM, Peter Keegan <peterlkee...@gmail.com > >wrote: > > > I'm doing a cross-core join query and the join query is 30X slower than > > each of the 2 individual queries. Here are the queries: > > > > Main query: http://localhost:8983/solr/mainindex/select?q=title:java > > QTime: 5 msec > > hit count: 1000 > > > > Sub query: http://localhost:8983/solr/subindex/select?q=+fld1:[0.1 TO > 0.3] > > QTime: 4 msec > > hit count: 25K > > > > Join query: > > > http://localhost:8983/solr/mainindex/select?q=title:java&fq={!joinfromIndex=mainindextoIndex=subindex > from=docid to=docid}fld1:[0.1 TO 0.3] > > QTime: 160 msec > > hit count: 205 > > > > Here are the index spec's: > > > > mainindex size: 117K docs, 1 segment > > mainindex schema: > > <field name="docid" type="int" indexed="true" stored="true" > > required="true" multiValued="false" /> > > <field name="title" type="text_en_splitting" indexed="true" > > stored="true" multiValued="false" /> > > <uniqueKey>docid</uniqueKey> > > > > subindex size: 117K docs, 1 segment > > subindex schema: > > <field name="docid" type="int" indexed="true" stored="true" > > required="true" multiValued="false" /> > > <field name="fld1" type="float" indexed="true" stored="true" > > required="false" multiValued="false" /> > > <uniqueKey>docid</uniqueKey> > > > > With debugQuery=true I see: > > "debug":{ > > "join":{ > > "{!join from=docid to=docid fromIndex=subindex}fld1:[0.1 TO 0.3]":{ > > "time":155, > > "fromSetSize":24742, > > "toSetSize":24742, > > "fromTermCount":117810, > > "fromTermTotalDf":117810, > > "fromTermDirectCount":117810, > > "fromTermHits":24742, > > "fromTermHitsTotalDf":24742, > > "toTermHits":24742, > > "toTermHitsTotalDf":24742, > > "toTermDirectCount":24627, > > "smallSetsDeferred":115, > > "toSetDocsAdded":24742}}, > > > > Via profiler and debugger, I see 150 msec spent in the outer > > 'while(term!=null)' loop in: JoinQueryWeight.getDocSet(). This seems > like a > > lot of time to join the bitsets. Does this seem right? > > > > Peter > > > > > -- Joel Bernstein Professional Services LucidWorks
