Comment 7 for bug 1805778

Sam, can this be retested, I think we were getting into dirty page write amplification because of using vfat on a tmpfs backing store file. I've reworked the test now to use bog standard vfat on a loopbacked file.

Fix committed: http://kernel.ubuntu.com/git/ubuntu/autotest-client-tests.git/commit/?id=e39a7d03a6dbda3039514096737d72150877017b