This fsync tester was initially written by Ted T'so and updated by Chris Mason.

The version in this repository is used by the Ceph project in testing and
has seen some updates to make it work better in that context.

The only change prior to the initial commit was a switch from 8GB to 256MB
for hte test file (because we often run tests against a small cluster, and 8GB
takes longer than is necessary to exercise the functionality we're worried about).