[LUCENE-2832] on Windows 64-bit, maybe we should default to a better maxBBufSize in MMapDirectory

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Fix Version/s: 4.9, 6.0
• Component/s: core/store
• Lucene Fields: New
• Assignee: Robert Muir
• Reporter: Robert Muir
• Created: 24/Dec/10 17:53
• Updated: 28/Aug/22 12:38

Description

Currently the default max buffer size for MMapDirectory is 256MB on 32bit and Integer.MAX_VALUE on 64bit:

public static final int DEFAULT_MAX_BUFF = Constants.JRE_IS_64BIT ? Integer.MAX_VALUE : (256 * 1024 * 1024);

But, in windows on 64-bit, you are practically limited to 8TB. This can cause problems in extreme cases, such as: http://www.lucidimagination.com/search/document/7522ee54c46f9ca4/map_failed_at_getsearcher

Perhaps it would be good to change this default such that its 256MB on 32Bit OR windows, but leave it at Integer.MAX_VALUE
on other 64-bit and "64-bit" (48-bit) systems.