An fq is still a single entry in your filterCache so from that perspective it's the same.
And to create that entry, you're still using all the underlying fields to search, so they have to be loaded just like they would be in a q clause. But really, the fundamental question here is why your design even has 1,500 fields and, more specifically, why you would want to search them all at once. From a 10,000 ft. view, that's a very suspect design. Best, Erick On Thu, Nov 19, 2015 at 4:06 PM, Walter Underwood <wun...@wunderwood.org> wrote: > The implementation for fq has changed from 4.x to 5.x, so I’ll let someone > else answer that in detail. > > In 4.x, the result of each filter query can be cached. After that, they are > quite fast. > > wunder > Walter Underwood > wun...@wunderwood.org > http://observer.wunderwood.org/ (my blog) > > >> On Nov 19, 2015, at 3:59 PM, Steven White <swhite4...@gmail.com> wrote: >> >> Thanks Walter. I see your point. Does this apply to fq as will? >> >> Also, how does one go about debugging performance issues in Solr to find >> out where time is mostly spent? >> >> Steve >> >> On Thu, Nov 19, 2015 at 6:54 PM, Walter Underwood <wun...@wunderwood.org> >> wrote: >> >>> 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 >>> >>> >
