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17e8e4245dSRobert Muir<html>
18e8e4245dSRobert Muir  <head>
19e8e4245dSRobert Muir    <title>
20e8e4245dSRobert Muir      miscellaneous
21e8e4245dSRobert Muir    </title>
22e8e4245dSRobert Muir  </head>
23e8e4245dSRobert Muir  <body>
24e8e4245dSRobert Muir
25f41eabdcSRobert Muir<h1>Misc Tools</h1>
26e8e4245dSRobert Muir
27e8e4245dSRobert MuirThe misc package has various tools for splitting/merging indices,
28e8e4245dSRobert Muirchanging norms, finding high freq terms, and others.
29e8e4245dSRobert Muir
30*a7747b63Szacharymorn<a id="DirectIODirectory"></a>
31*a7747b63Szacharymorn<h2>DirectIODirectory</h2>
32e8e4245dSRobert Muir
33e8e4245dSRobert Muir<p>
34*a7747b63Szacharymorn{@link org.apache.lucene.misc.store.DirectIODirectory} is a Directory implementation that bypasses the
35e8e4245dSRobert MuirOS's buffer cache (using direct IO) for any IndexInput and IndexOutput
36e8e4245dSRobert Muirused during merging of segments larger than a specified size (default
37e8e4245dSRobert Muir10 MB).  This avoids evicting hot pages that are still in-use for
38e8e4245dSRobert Muirsearching, keeping search more responsive while large merges run.
39e8e4245dSRobert Muir
40e8e4245dSRobert Muir<p>
41ebc87a8aSzacharymornSee <a target="_top" href="http://blog.mikemccandless.com/2010/06/lucene-and-fadvisemadvise.html">this blog post</a>
42e8e4245dSRobert Muirfor details.
43e8e4245dSRobert Muir
44e8e4245dSRobert Muir</body>
45e8e4245dSRobert Muir
46e8e4245dSRobert Muir</html>
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