If we want a longer runtime than that, run it several times in
sequence.
This limits the amount of disk space we'll consume.
Signed-off-by: Sage Weil <sage@redhat.com>
Because it needs the thrasher to have min_in: 4 otherewise k=3,m=1 will
block.
http://tracker.ceph.com/issues/9648Fixes: #9648
Signed-off-by: Loic Dachary <loic-201408@dachary.org>