[LUCENE-2060] CMS should default its maxThreadCount to 1 (not 3)

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.9.3, 3.0
• Component/s: core/index
• Lucene Fields: New
• Assignee: Michael McCandless
• Reporter: Michael McCandless
• Created: 13/Nov/09 13:11
• Updated: 28/Aug/22 12:14
• Resolved: 01/Jun/10 16:40

Description

From rough experience, I think the current default of 3 is too large. I think we get the most bang for the buck going from 0 to 1.

I think this will especially impact optimize on an index with many segments – in this case the MergePolicy happily exposes concurrency (multiple pending merges), and CMS will happily launch 3 threads to carry that out.