Thanks for clarifying Yonik.
On Sat, Feb 25, 2012 at 3:57 PM, Yonik Seeley <yo...@lucidimagination.com> wrote: > On Sat, Feb 25, 2012 at 3:39 PM, Jamie Johnson <jej2...@gmail.com> wrote: >> "Unfortunately, Apache Solr still uses this horrible code in a lot of >> places, leaving us with a major piece of work undone. Major parts of >> Solr’s facetting and filter caching need to be rewritten to work per >> atomic segment! For those implementing plugins or other components for >> Solr, SolrIndexSearcher exposes a “atomic view” of its underlying >> reader via SolrIndexSearcher.getAtomicReader()." > > Some of this is just a misunderstanding, and some of it is a > difference of opinion. > > Solr uses a top-level FieldCache entry for certain types of faceting, > but it's optional. Solr can also use per-segment FieldCache entries > when faceting. The reason we haven't removed the top-level FieldCache > faceting is that it's faster unless you are doing near-realtime (NRT) > search (due to the cost of merging terms across segments). Top level > fieldcache entries are also more memory efficient for Strings as > string values are not repeated across each segment. The right > approach depends on the specific use-case, and Solr will continue to > strive to have faceting algorithms optimized for both NRT and non-NRT. > > -Yonik > lucenerevolution.com - Lucene/Solr Open Source Search Conference. > Boston May 7-10
