Okay I think I found it. Let me know if this makes sense (also for those curious about this).
1) The IndexSearcher will create a FilteredQuery using the RANDOM_ACCESS_STRATEGY by default (IndexSearcher#wrapFilter). 2) When the searcher requests the scorer, the FilteredQuery uses the FilterStrategy to retrieve the scorer (FilterStrategy#filteredScorer) 3) The RandomAccessFilterStrategy seems to use a heuristic of whether or not to use the leapfrog strategy when the first document returned by the filter is < 100. (RandomAccessFilterStrategy#useRandomAccess). My simple test had < 100 docs hence why it never went down this leap frog approach in my debugging. Next question though is what is the significance of this < 100? Is this supposed to be a heuristic for determining the sparseness of the filter bit set? Thanks again Amit On Sat, Oct 20, 2012 at 7:12 PM, Amit Nithian <anith...@gmail.com> wrote: > Thanks. So I was poking through this and see that the filters are > calculated up front and stored as docsets that get intersected and > passed into Lucene in the filter. The question though is that > somewhere in the IndexSearcher and somewhere into the scorer it does > this but I can't quite find where. > > Thanks > Amit > > On Sat, Oct 20, 2012 at 5:22 PM, Mikhail Khludnev > <mkhlud...@griddynamics.com> wrote: >> Amit, >> >> Sure. this method >> https://github.com/apache/lucene-solr/blob/trunk/solr/core/src/java/org/apache/solr/search/SolrIndexSearcher.java#L796beside >> some other stuff calculates fq's docset intersection which is >> supplied into filtered search call >> https://github.com/apache/lucene-solr/blob/trunk/solr/core/src/java/org/apache/solr/search/SolrIndexSearcher.java#L1474 >> >> You are welcome. >> >> On Sun, Oct 21, 2012 at 12:00 AM, Amit Nithian <anith...@gmail.com> wrote: >> >>> Hi all, >>> >>> Quick question. I've been reading up on the filter query and how it's >>> implemented and the multiple articles I see keep referring to this >>> notion of leap frogging and filter query execution in parallel with >>> the main query. Question: Can someone point me to the code that does >>> this so I can better understand? >>> >>> Thanks! >>> Amit >>> >> >> >> >> -- >> Sincerely yours >> Mikhail Khludnev >> Tech Lead >> Grid Dynamics >> >> <http://www.griddynamics.com> >> <mkhlud...@griddynamics.com>
