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Earwin Burrfoot commented on LUCENE-1743: ----------------------------------------- bq. My problem was more with all these small files like segments_XXXX and segments.gen or *.del files. They are small and only used one time. I can only reiterate my point. These files aren't opened like 10k files per second, so your win is going to be in the order of microseconds per reopen - at the cost of increased complexity. > MMapDirectory should only mmap large files, small files should be opened > using SimpleFS/NIOFS > --------------------------------------------------------------------------------------------- > > Key: LUCENE-1743 > URL: https://issues.apache.org/jira/browse/LUCENE-1743 > Project: Lucene - Java > Issue Type: Improvement > Components: Store > Affects Versions: 2.9 > Reporter: Uwe Schindler > Assignee: Uwe Schindler > Fix For: 3.1 > > > This is a followup to LUCENE-1741: > Javadocs state (in FileChannel#map): "For most operating systems, mapping a > file into memory is more expensive than reading or writing a few tens of > kilobytes of data via the usual read and write methods. From the standpoint > of performance it is generally only worth mapping relatively large files into > memory." > MMapDirectory should get a user-configureable size parameter that is a lower > limit for mmapping files. All files with a size<limit should be opened using > a conventional IndexInput from SimpleFS or NIO (another configuration option > for the fallback?). -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online. --------------------------------------------------------------------- To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org For additional commands, e-mail: java-dev-h...@lucene.apache.org