# uname -a; dd if=/dev/xvda iflag=direct bs=16384 of=/dev/null & DD_PID=$!; sleep 1 && ./getdelays -di -p $DD_PID; kill $DD_PID; wait
Linux cass-perf-josh--useast1c-i-001d269b456aa2773 4.13.0-32-generic #35~lp1747769 SMP Thu Feb 8 17:37:46 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
[1] 9578
print delayacct stats ON
printing IO accounting
PID	9578


CPU             count     real total  virtual total    delay total  delay average
                 2621              0       23341678         709838          0.000ms
IO              count    delay total  delay average
                 2620      975185892              0ms
SWAP            count    delay total  delay average
                    0              0              0ms
RECLAIM         count    delay total  delay average
                    0              0              0ms
dd: read=42942464, write=0, cancelled_write=0
[1]+  Terminated              dd if=/dev/xvda iflag=direct bs=16384 of=/dev/null