I know how to index a document with a boost but am still not sure whether I'll see a search performance improvement with it. The initial decision to use a boost function at search-time was made to preserve the flexibility to tweak the function without having to a full reindex. I no longer need that flexibility so was wondering if I would get better performance by implement the boost at index-time.
On Fri, Jun 4, 2010 at 11:48 PM, Jonathan Rochkind <rochk...@jhu.edu> wrote: > The SolrRelevancyFAQ does suggest that both index-time and search-time > boosting can be used to boost the score of newer documents, but doesn't > suggest what reasons/contexts one might choose one vs the other. It only > provides an example of search-time boost though, so it doesn't answer the > question of how to do an index time boost, if that was a question. > > > http://wiki.apache.org/solr/SolrRelevancyFAQ#How_can_I_boost_the_score_of_newer_documents > > Sorry, this doesn't answer your question, but does contribute the fact that > some author of the FAQ at some point considered index-time boost not > neccesarily unreasonable. > ________________________________________ > From: Asif Rahman [a...@newscred.com] > Sent: Friday, June 04, 2010 11:31 PM > To: solr-user@lucene.apache.org > Subject: Re: Index-time vs. search-time boosting performance > > It seems like it would be far more efficient to calculate the boost factor > once and store it rather than calculating it for each request in real-time. > Some of our queries match tens of thousands if not hundreds of thousands of > documents in a 15GB index. However, I'm not well-versed in lucene > internals > so I may be misunderstanding what is going on here. > > > On Fri, Jun 4, 2010 at 8:31 PM, Jay Hill <jayallenh...@gmail.com> wrote: > > > I've done a lot of recency boosting to documents, and I'm wondering why > you > > would want to do that at index time. If you are continuously indexing new > > documents, what was "recent" when it was indexed becomes, over time "less > > recent". Are you unsatisfied with your current performance with the boost > > function? Query-time recency boosting is a fairly common thing to do, > and, > > if done correctly, shouldn't be a performance concern. > > > > -Jay > > http://lucidimagination.com > > > > > > On Fri, Jun 4, 2010 at 4:50 PM, Asif Rahman <a...@newscred.com> wrote: > > > > > Perhaps I should have been more specific in my initial post. I'm doing > > > date-based boosting on the documents in my index, so as to assign a > > higher > > > score to more recent documents. Currently I'm using a boost function > to > > > achieve this. I'm wondering if there would be a performance > improvement > > if > > > instead of using the boost function at search time, I indexed the > > documents > > > with a date-based boost. > > > > > > On Fri, Jun 4, 2010 at 7:30 PM, Erick Erickson < > erickerick...@gmail.com > > > >wrote: > > > > > > > Index time boosting is different than search time boosting, so > > > > asking about performance is irrelevant. > > > > > > > > Paraphrasing Hossman from years ago on the Lucene list (from > > > > memory). > > > > > > > > ...index time boosting is a way of saying this documents' > > > > title is more important than other documents' titles. Search > > > > time boosting is a way of saying "I care about documents > > > > whose titles contain this term more than other documents > > > > whose titles may match other parts of this query".... > > > > > > > > HTH > > > > Erick > > > > > > > > On Fri, Jun 4, 2010 at 5:10 PM, Asif Rahman <a...@newscred.com> > wrote: > > > > > > > > > Hi, > > > > > > > > > > What are the performance ramifications for using a function-based > > boost > > > > at > > > > > search time (through bf in dismax parser) versus an index-time > boost? > > > > > Currently I'm using boost functions on a 15GB index of ~14mm > > documents. > > > > > Our > > > > > queries generally match many thousands of documents. I'm wondering > > if > > > I > > > > > would see a performance improvement by switching over to index-time > > > > > boosting. > > > > > > > > > > Thanks, > > > > > > > > > > Asif > > > > > > > > > > -- > > > > > Asif Rahman > > > > > Lead Engineer - NewsCred > > > > > a...@newscred.com > > > > > http://platform.newscred.com > > > > > > > > > > > > > > > > > > > > > -- > > > Asif Rahman > > > Lead Engineer - NewsCred > > > a...@newscred.com > > > http://platform.newscred.com > > > > > > > > > -- > Asif Rahman > Lead Engineer - NewsCred > a...@newscred.com > http://platform.newscred.com > -- Asif Rahman Lead Engineer - NewsCred a...@newscred.com http://platform.newscred.com
