Subject: [PATCH] WC rep cache optimization for some file systems like NTFS on Windows

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   WC rep cache optimization for some file systems like NTFS on Windows
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Hello,

Please review my patch (see attached file patch.txt). It improve svn client
performance on file systems like NTFS on Windows. Maybe on some other file
systems, e.g. NFS, but I didn't test it. This patch switch rep cache db
journal mode from DELETE (by default) to PERSISTENT. For more info about
journal modes in SQLite see
http://www.sqlite.org/pragma.html#pragma_journal_mode.

I have tested this patch on my desktop (Core i7-2600, 16Gb, Windows 7 x64
Enterprise) for two disk drives: standard and ssd. For tests I used
Subversion Benchmark Tool, see
https://ctf.open.collab.net/sf/frs/do/listReleases/projects.csvn/frs.subversion_benchmark_tool.
For tested application I used svn 1.8.0 from trunk, revision 1387070.

Subversion Benchmark Tool tests, total results:

Standard disk:
svn.r1387070 - 3:05.895
svn.patch - 2:06.548

SSD disk:
svn.r1387070 - 2:11.504
svn.patch - 1:38.397

For detailed results see attached files: std.180.txt, std.patch.txt,
ssd.180.txt, ssd.patch.txt