On Apr 14, 2010, at 11:06 AM, Chris Male wrote: > Hi, > > My understanding of the benefits of the new algorithm is that it means a > lower tier level resulting in fewer boxes, but more documents inside those > boxes that are outside of the search radius. > > While having fewer boxes means fewer term queries to make against the index, > more documents means more costly calculations to filter out those extraneous > documents. > > For those doing just Cartesian Tier filtering it seems like the new approach > is a win, but for those doing distance calculations on those documents > passing the filter, it seems to come at a cost.
Currently, this is only used for filtering. AIUI, Tiers aren't really that useful for distance calculations, are they? After all, all you have is a box id and you'd have to reverse out the calc of that to be able to calc a distance, no? Perhaps I'm missing something. I'm not sure, however, that it is a win for filtering. It seems like you end up including docs in the result set that should be in there. I'll wait for Nicolas' summary table, but I'm inclined to revert and then someone can refactor if they want to offer alternate implementations. -Grant --------------------------------------------------------------------- To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org For additional commands, e-mail: java-dev-h...@lucene.apache.org
