improve test to catch more failure modes (both races and hangs)
improve test to catch more failure modes (both races and hangs)

sdalton1/legion,StanfordLegion/legion,chuckatkins/legion,StanfordLegion/legion,sdalton1/legion,sdalton1/legion,StanfordLegion/legion,chuckatkins/legion,StanfordLegion/legion,sdalton1/legion,StanfordLegion/legion,chuckatkins/legion,chuckatkins/legion,sdalton1/legion,chuckatkins/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,sdalton1/legion,chuckatkins/legion,chuckatkins/legion