On Fri, Sep 26, 2014 at 4:38 PM, Tom Burton-West <tburt...@umich.edu> wrote: > Hi Yonik, > > I'm still confused. > > suspect don't understand how paging and caching interact. I probably need > to walk through the code. Is there a unit test that exercises > SolrIndexSearcher.getDocListC or a good unit test to use as a base to write > one? > > > Part of what confuses me is whether what gets cached always starts at row 1 > of results.
Yes, we always cache from the first row. Asking for rows 91-100 requires collecting 1-100 (and it's the latter we cache - ignoring deep paging). It's also just ids (and optionally scores) that are cached... so either 4 bytes or 8 bytes per document cached, depending on if you ask for scores back. queryWindowSize just rounds up the upper bound. > I'll try to explain my confusion. > Using the defaults in the solrconfig example: > <queryResultWindowSize>20</queryResultWindowSize> > <queryResultMaxDocsCached>200</queryResultMaxDocsCached> > > If I query for start=0, rows =10 Solr fetches 20 results and caches them. > If I query for start =11 rows =10 Solr read rows 11-20 from cache Correct. > What happens when I query for start = 21 rows= 10? > I thought that Solr would then fetch rows 21-40 into the queryResultCache. > Is this wrong? It will result in a cache miss and we'll collect 0-40 and cache that. > If I query for start =195 rows =10 does Solr cache rows 195-200 but go to > disk for rows over 200 (queryResultMaxDocsCached=200)? Or does Solr skip > caching altogether for rows over 200 Probably the latter... it's an edge case so I'd have to check the code to know for sure if the check is pre or post rounding up. -Yonik http://heliosearch.org - native code faceting, facet functions, sub-facets, off-heap data --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
