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Christopher Currens commented on LUCENENET-425: ----------------------------------------------- On a 1.18GB index of only one text field: MMap Dir: 74 FS Dir: 34 ----------- MMap Dir: 79 FS Dir: 29 Press any key to continue . . . Same index, order of search changed: FS Dir: 25 MMap Dir: 110 ----------- FS Dir: 112 MMap Dir: 78 Press any key to continue . . . On a 241MB index of text and binary data (used a field selector to only get the text field): FS Dir: 151 MMap Dir: 679 ----------- FS Dir: 130 MMap Dir: 627 Press any key to continue . . . Same index, order of search changed: MMap Dir: 867 FS Dir: 134 ----------- MMap Dir: 600 FS Dir: 135 Press any key to continue . . . The second index, while smaller, requires a lot more seeking, due to the amount of fields per doc (anywhere from 15-30 fields per doc). Seems it would be a more realistic index to search. > MMapDirectory implementation > ---------------------------- > > Key: LUCENENET-425 > URL: https://issues.apache.org/jira/browse/LUCENENET-425 > Project: Lucene.Net > Issue Type: New Feature > Affects Versions: Lucene.Net 2.9.4g > Reporter: Digy > Priority: Trivial > Fix For: Lucene.Net 2.9.4g > > Attachments: MMapDirectory.patch > > > Since this is not a direct port of MMapDirectory.java, I'll put it under > "Support" and implement MMapDirectory as > {code} > public class MMapDirectory:Lucene.Net.Support.MemoryMappedDirectory > { > } > {code} > If a Mem-Map can not be created(for ex, if the file is too big to fit in 32 > bit address range), it will default to FSDirectory.FSIndexInput > In my tests, I didn't see any performance gain in 32bit environment and I > consider it as better then nothing. > I would be happy if someone could send test results on 64bit platform. > DIGY -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira