Checks absolute times elapsed in a VM against currentmillis.com

time_is_broken_abandon_hope.sh

#!/bin/bash

SAMPLES=5
OVERHEAD=600 # about 600ms of overhead from AU for the service below

function remote_millis() {
  curl --silent http://currentmillis.com/api/millis-since-unix-epoch.php
}

for i in {1..10} ; do
  for u in $(eval echo "{1..$SAMPLES}") ; do
    echo -n "sleeping for $i seconds... "
    before=$(remote_millis)
    localtimer=$(TIMEFORMAT=%R; (time sleep $i) 2>&1)
    after=$(remote_millis)
    echo -n "${localtimer}s elapsed locally, "
    echo "$(($after - $before - $OVERHEAD))ms remotely"
  done
done