With one field in qf for a single-term query, Solr is fetching one posting list. With 1500 fields, it is fetching 1500 posting lists. It could easily be 1500 times slower.
It might be even slower than that, because we can’t guarantee that: a) every algorithm in Solr is linear, b) that all those lists will fit in memory. wunder Walter Underwood wun...@wunderwood.org http://observer.wunderwood.org/ (my blog) > On Nov 19, 2015, at 3:46 PM, Steven White <swhite4...@gmail.com> wrote: > > Hi everyone > > What is considered too many fields for qf and fq? On average I will have > 1500 fields in qf and 100 in fq (all of which are OR'ed). Assuming I can > (I have to check with the design) for qf, if I cut it down to 1 field, will > I see noticeable performance improvement? It will take a lot of effort to > test this which is why I'm asking first. > > As is, I'm seeing 2-5 sec response time for searches on an index of 1 > million records with total index size (on disk) of 4 GB. I gave Solr 2 GB > of RAM (also tested at 4 GB) in both cases Solr didn't use more then 1 GB. > > Thanks in advanced > > Steve
