A number of build failures on Windows systems seem to stem from file locking issues.

Working theory: Our test harness assumes that files owned by a process (usually mongod) will be unlocked as soon as the process exits.

Windows guarantees that the OS will unlock files after process termination, but makes no guarantees about when they will be unlocked. On a loaded system it may not be immediate.

Test failures we believe are due to our test framework assuming that the files are immediately unlocked on exit:

Buildbot V2.4 Windows 64-bit 2008R2+

• test_7 js suite failing between tests
  • Build #89
  • Build #87
  • Build #81
  • Build #80
  • Build #75
  • Build #55

Errors include:

WindowsError: [Error 5] Access is denied: '/data/db/sconsTests//loadserverscripts.0'

WindowsError: [Error 32] The process cannot access the file because it is being used by another process: '/data/db/sconsTests//loadserverscripts.0'

Buildbot V2.4 Windows 64-bit

• Build #77

WindowsError: [Error 5] Access is denied: '/data/db/sconsTests//local.0'

This one different: not a test framework error, but rather a failure within a test.

Buildbot V2.4 Windows 32-bit

• http://buildlogs.mongodb.org/V2.4%20Windows%2032-bit/builds/185/test/replica%20sets/replset1.js "Unclean shutdown detected" when mongod restarted.
  • test didn't wait until previous mongod was fully shut down?