killcache
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What's the equivalent to "echo 3 > /proc/sys/vm/drop_caches" on Windows?
(flushing read cache)

These do *not* work:

http://technet.microsoft.com/en-us/sysinternals/bb897438
http://technet.microsoft.com/en-us/sysinternals/bb897561
http://chadaustin.me/flushmem/
http://www.microsoft.com/download/en/details.aspx?id=17657 (consume.exe, also
in Windows SDK).

sync only flushes write cache. cacheset doesn't seem to do too much of
anything.

consume sorta-works, but it destroys your machine so badly that it'd be faster
to just reboot to get a cold cache. consume and flushmem are both trying to
consume more resources than are available and hope that as a side-effect the
disk cache gets more-or-less-flushed.

Presumably since consuming all system resources is an <ahem> _strategy_ that a
lot of Windows client software employs, the OS is pretty decent at thwarting
that sort behaviour and keeping the cache relatively hot.

Another Internet-recommend solution is to use SetSystemFileCacheSize (after
acquiring SE_INCREASE_QUOTA_NAME privilege). This doesn't appear to have any
appreciable effect. It's not clear from the documentation, it may again only
be flushing the write cache.


So what *does* work?
--------------------

1. Working on a separate hard drive, and in the Administration interface,
   changing the drive letter to something else, and then changing it back
   (i.e. unmount, remount). This doesn't work for the system drive, but it's
   pretty decent to get your project out of cache if you have a second drive.
   Unfortunately, not very easy to use from the command line and doesn't
   completely simulate cold cache because OS services will still be hot.

2. Somewhat surprisingly, opening a file handle to the root of the drive
   _without_ FILE_SHARE_WRITE (i.e. only FILE_SHARE_READ) per
   http://stackoverflow.com/a/8113490.

killcache implements #2, and seems to work very effectively (or at least Works-
On-My-Machine) for Win7 x64.

Build and run
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In a vsvars32 prompt (i.e. with cl and link in the path):

  ...\killcache>m.bat
  ...\killcache>killcache c

And then re-run your app.