[SOLR-8988] Improve facet.method=fcs performance in SolrCloud

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 5.5, 6.0
• Fix Version/s: 6.1
• Assignee: Dennis Gove
• Reporter: Keith Laban
• Created: 14/Apr/16 18:46
• Updated: 11/Dec/17 17:41
• Resolved: 23/May/16 19:37

Description

This relates to SOLR-8559 – which improves the algorithm used by fcs faceting when facet.mincount=1

This patch allows facet.mincount to be sent as 1 for distributed queries. As far as I can tell there is no reason to set facet.mincount=0 for refinement purposes . After trying to make sense of all the refinement logic, I cant see how the difference between no value and value=0 would have a negative effect.

Test perf:

• ~15million unique terms
• query matches ~3million documents

Params:

facet.mincount=1
facet.limit=500
facet.method=fcs
facet.sort=count

Average Time Per Request:

• Before patch: ~20seconds
• After patch: <1 second

Note: all tests pass and in my test, the output was identical before and after patch.

Issue Links

• is part of: SOLR-11711 distributed pivot & field facets can processes excessive docs unneccessarily due to internal mincount=0
• is related to: SOLR-11711 distributed pivot & field facets can processes excessive docs unneccessarily due to internal mincount=0