[LUCENE-893] Increase buffer sizes used during searching

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 2.1
• Component/s: core/search
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Michael McCandless
• Created: 25/May/07 19:43
• Updated: 28/Aug/22 11:37
• Resolved: 10/Mar/13 13:20

Description

Spinoff of LUCENE-888.

In LUCENE-888 we increased buffer sizes that impact indexing and found
substantial (10-18%) overall performance gains.

It's very likely that we can also gain some performance for searching
by increasing the read buffers in BufferedIndexInput used by
searching.

We need to test performance impact to verify and then pick a good
overall default buffer size, also being careful not to add too much
overall HEAP RAM usage because a potentially very large number of
BufferedIndexInput instances are created during searching
(# segments X # index files per segment).