The following tests in the testsuite have race conditions:

The following tests in the testsuite have race conditions:
1) Test that the primary mirror image cannot be removed while
   the mirror set is sync'ing.
2) Test that you cannot start a second mirror up-convert while
   one is already in progress.

The trouble is that if the sync/conversion finishes before the
tests occur, the tests will fail by why of success where there
should have been failure.  This means the sync/conversion must
happen very quickly, but this is possible because the test
mirrors we are creating are so small.

In order to decrease the likelyhood of these test failing (or
more correctly, failing to test the right thing), I've increase
the size of the mirrors.  It will still be remotely possible that
the tests will fail (by way of failing to test the right thing).
If this continues to happen, more involved mechanisms will need
to be put in place.  (Perhaps these will still be created, but
this change should be a remedy until that time.)