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Greg Miller commented on LUCENE-10302: -------------------------------------- {quote}I have the start of some code in progress I can share to anyone interested. I'm not sure when I'll get back to this. {quote} [~dsmiley] I'd be interested in exploring this a little bit as I have some spare time. I'm not going to assign it to myself since I'm not sure how much time I'll have for it, but I'd be curious to take a look at the progress you've made if you don't mind posting. > PriorityQueue: optimize where we collect then iterate by using O(N) heapify > --------------------------------------------------------------------------- > > Key: LUCENE-10302 > URL: https://issues.apache.org/jira/browse/LUCENE-10302 > Project: Lucene - Core > Issue Type: Improvement > Reporter: David Smiley > Priority: Major > > Looking at LUCENE-8875 (LargeNumHitsTopDocsCollector.java ) I got to > wondering if there was faster-than O(N*log(N)) way of loading a PriorityQueue > when we provide a bulk array to initialize the heap/PriorityQueue. It turns > out there is: the JDK's PriorityQueue supports this in its constructors, > referring to "This classic algorithm due to Floyd (1964) is known to be > O(size)" -- heapify() method. There's > [another|https://www.geeksforgeeks.org/building-heap-from-array/] that may > or may not be the same; I didn't look too closely yet. I see a number of > uses of Lucene's PriorityQueue that first collects values and only after > collecting want to do something with the results (typical / unsurprising). > This lends itself to a builder pattern that can look similar to > LargeNumHitsTopDocsCollector in terms of first having an array used like a > list and then move over to the PriorityQueue if/when it gets full (it may > not). -- This message was sent by Atlassian Jira (v8.20.1#820001) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org