I have an idea for a Solr feature, but to know whether it's at all viable, I need a question about Lucene operation answered.
In recent versions of Solr, if a field is not stored, not indexed, but does have docValues, the originally indexed data sent for that field will be returned in search results. In older versions (not sure which ones) a field must be stored to be returned. Let's say that such a field contains a very large amount of data in every document. Normally, this would affect OS disk cache efficiency for general queries, because the docValues data for the field would need to be read in order to be included in search results. Reading that large amount of data can pollute the disk cache. If the system is in a low-memory situation, that can affect performance. What happens if every query has an explicit list of fields to return in results, and the list of fields does NOT include this field that contains a large amount of data in docValues? Does this mean that the docValues data for the field I've mentioned is never read, and has no effect on OS disk cache efficiency? Or would Lucene read the docValues data even though it doesn't include it in results? Thanks, Shawn --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
