I don't think it makes a difference if some people think docValues should never be used for value-retrieval. When that performance drop occurred due to those changes, I'm sure it would have affected sorting & faceting as well as value-retrieval. Some more than others perhaps. I don't see any disagreement about improving docValues in the ways you suggest. If theoretically you proposed a change that helped the value-retrieval use-case and hurt the non-controversial use-cases then I could see why you want to raise this issue more publicly like you're doing here.
~ David On Mon, Sep 24, 2018 at 8:40 AM Toke Eskildsen <[email protected]> wrote: > The Solr 7 switch to iterative API for Doc Values > https://issues.apache.org/jira/browse/LUCENE-7407 > meant a severe performance regression for Solr export and document > retrieval with our web archive index, which is distinguished by having > quite large segments (300M docs / 900GB) and using primarily doc values > to hold field content. > > Technically there is a working patch > https://issues.apache.org/jira/browse/LUCENE-8374 > but during discussion of performance measurements elsewhere > https://github.com/mikemccand/luceneutil/issues/23 > it came up that doc values are not intended for document retrieval and > as such that Lucene should not be optimized towards that. > > > From my point of view, using doc values to build retrieval documents is > quite natural: The data are there, so making a double representation by > also making them stored seems a waste of space. > > If this is somehow a misuse of Doc Values, maybe I could be explained > what the problem is or directed towards more information? > > - Toke Eskildsen, Royal Danish Library > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > > -- Lucene/Solr Search Committer, Consultant, Developer, Author, Speaker LinkedIn: http://linkedin.com/in/davidwsmiley | Book: http://www.solrenterprisesearchserver.com
