Optimizing an index forces segments to merge. Usually, segments are merged automatically based on your mergeFactor setting. During a merge documents flagged for deletion are really purged and the number of segments is reduces which improves search performance. There are some good pages on mergeFactor around. Haven't got a link at hand.
> One more question - what does optimization do? Maybe to be a little more > precise - what happens to the index that requires optimizaion (what is the > problem and how does optimization solve it). > > Aaron Chmelik > Web Designer & Programmer > email: aaron.chme...@gmail.com > website: http://webdesign.aaronchmelik.com > phone: 651.757.5979 > > On Thu, May 26, 2011 at 4:27 PM, Aaron Chmelik <aaron.chme...@gmail.com>wrote: > > Thanks! coming from Sphinx, with seperate delta index files. Thanks for > > the info! > > > > Aaron Chmelik > > Web Designer & Programmer > > email: aaron.chme...@gmail.com > > website: http://webdesign.aaronchmelik.com > > phone: 651.757.5979 > > > > > > On Thu, May 26, 2011 at 4:21 PM, Markus Jelsma > > <markus.jel...@openindex.io > > > > > wrote: > >> Define reindexing. Every new document is indexed and existing documents > >> are > >> deleted and indexed as if it is a new document. Completely reindexing > >> from scratch is only required if breaking changes are made to the > >> schema or if you > >> upgrade to a new version that uses another format and isn't able to > >> convert. > >> > >> To my knowledge and experience, it is perfectly sane to never do a > >> complete > >> reindex and still accept incremental updates. Just do an optimize once > >> in a > >> while and you're good to go. > >> > >> > I've been trying to find a concise explanation of this, and seem to so > >> > >> far > >> > >> > have missed it. (Google, etc). What is the purpose/need to reindex a > >> > >> solr > >> > >> > index? How do you determine what provides the best performance? What > >> > detrimental affects occur if you operate off of delta indexes? > >> > > >> > Aaron Chmelik > >> > Web Designer & Programmer > >> > email: aaron.chme...@gmail.com > >> > website: http://webdesign.aaronchmelik.com > >> > phone: 651.757.5979
