I don't have enough knowledge to give the greenlight on this, but on a high level it seems reasonable. This question is probably more appropriate to surface on the dev mailing list rather than the users mailing list. Hopefully you get more thoughts on your patch suggestion there
-Kevin From: users@solr.apache.org At: 03/25/25 20:24:32 UTC-4:00To: users@solr.apache.org Cc: chirayu.sama...@bloomreach.com Subject: Performance issue: distributed grouping + dense vector search Hi All, When running vector search with grouping in multi-shard setting, the KnnFloatVectorQuery is executed (2+rows) times. The culprit is this function call in https://github.com/apache/solr/blob/main/solr/core/src/java/org/apache/solr/sear ch/grouping/distributed/command/TopGroupsFieldCommand.java#L202 if (needScores) { for (GroupDocs<?> group : topGroups.groups) { TopFieldCollector.populateScores(group.scoreDocs, searcher, query); } } Where https://github.com/apache/lucene/blob/main/lucene/core/src/java/org/apache/lucen e/search/TopFieldCollector.java#L403 does final Weight weight = searcher.createWeight(searcher.rewrite(query), ScoreMode.COMPLETE, 1); Here, if the query is KnnFloatVectorQuery, *searcher.rewrite(query) *will execute the same vector search for each topGroups.groups a simple fix could be moving *searcher.rewrite(query) *out of the topGroups.groups loop. Thoughts? Best, Yue
