OurBigBook Docs
stackoverflow.com/questions/18215389/how-do-i-measure-request-and-response-times-at-once-using-curl is a useful one if the server is slow:
curl -o /dev/null -s -w 'Establish Connection: %{time_connect}s\nTTFB: %{time_starttransfer}s\nTotal: %{time_total}s\n' http://localhost:3000