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ASF subversion and git services commented on LUCENE-7097: --------------------------------------------------------- Commit 8cbe4713775565a3194e29b90747f59fe2ffe3f1 in lucene-solr's branch refs/heads/master from Mike McCandless [ https://git-wip-us.apache.org/repos/asf?p=lucene-solr.git;h=8cbe471 ] LUCENE-7097: let IntroSorter go 2X deeper in quicksort before switching to heapsort > Can we increase the stack depth before Introsorter switches to heapsort? > ------------------------------------------------------------------------ > > Key: LUCENE-7097 > URL: https://issues.apache.org/jira/browse/LUCENE-7097 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Michael McCandless > Assignee: Michael McCandless > Fix For: trunk, 6.1 > > Attachments: LUCENE-7097.patch > > > Introsort is a "safe" quicksort: it uses quicksort but detects when an > adversary is at work and cuts over to heapsort at that point. > The description at https://en.wikipedia.org/wiki/Introsort shows the cutover > as 2X log_2(N) but our impl ({{IntroSorter}}) currently uses just log_2. > So I tested using 2X log_2 instead, and I see a decent (~5.6%, from 98.2 sec > to 92.7 sec) speedup in the time for offline sorter to sort when doing the > force merge of 6.1 LatLonPoints from the London UK benchmark. > Is there any reason not to switch? I know this means 2X the stack required, > but since this is log_2 space that seems fine? -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org