On Wed, 2020-02-05 at 13:00 +0100, Emir Arnautović wrote: > I was thinking in that direction. Do you know where it is in the > codebase or which structure is used - I am guessing some array of > objects?
Yeah. More precisely a priority queue of Objects, initialized with sentinel Objects. rows=1000000 is bad both from a memory allocation POW and because the heap-structure of the priority queue implementation has extremely bad memory locality when it is being updated. I performed some measurements and did some experiments a few years ago: https://sbdevel.wordpress.com/2015/10/05/speeding-up-core-search/ and there is https://issues.apache.org/jira/browse/LUCENE-8875 which takes care of the Sentinel thing in solr 8.2. - Toke Eskildsen, Royal Danish Library
