The Solr instance is single-shard. Index size is around 20G and total doc # is about 12 million. Below are the histograms for the three facet fields in my query. Thanks.
On Thu, Mar 5, 2015 at 11:57 PM, Toke Eskildsen <t...@statsbiblioteket.dk> wrote: > On Thu, 2015-03-05 at 21:14 +0100, lei wrote: > > You present a very interesting observation. I have not noticed what you > describe, but on the other hand we have not done comparative speed > tests. > > > q=*:*&fq=country:"US"&fq=category:112 > > First observation: Your query is '*:*, which is a "magic" query. Non-DV > faceting has optimizations both for this query (although that ought to > be disabled due to the fq) and for the "inverse" case where there are > more hits than non-hits. Perhaps you could test with a handful of > queries, which has different result sizes? > > > &facet=on&facet.sort=index&facet.mincount=1&facet.limit=2000 > > The combination of index order and a high limit might be an explanation: > When resolving the Strings of the facet result, non-DV will perform > ordinal-lookup, which is fast when done in monotonic rising order > (sort=index) and if the values are close (limit=2000). I do not know if > DV benefits the same way. > > On the other hand, your limit seems to apply only to material, so it > could be that the real number of unique values is low and you just set > the limit to 2000 to be sure you get everything? > > > &facet.field=manufacturer&facet.field=seller&facet.field=material > > > &f.manufacturer.facet.mincount=1&f.manufacturer.facet.sort=count&f.manufacturer.facet.limit=100 > > > &f.seller.facet.mincount=1&f.seller.facet.sort=count&f.seller.facet.limit=100 > > &f.material.facet.mincount=1&sort=score+desc > > How large is your index in bytes, how many documents does it contain and > is it single-shard or cloud? Could you paste the loglines containing > "UnInverted field", which describes the number of unique values and size > of your facet fields? > > - Toke Eskildsen, State and University Library, Denmark > >
