linux curl request stats

I use this when I need a quick performance baseline for an endpoint — how long DNS takes, how long the connection takes, how long to first byte. The format file approach gives you a clean breakdown of each phase, which is far more useful than just watching the total time.

• Specify response format in file

$ vi responseFormat

     time_namelookup:  %{time_namelookup}s\n
        time_connect:  %{time_connect}s\n
     time_appconnect:  %{time_appconnect}s\n
    time_pretransfer:  %{time_pretransfer}s\n
       time_redirect:  %{time_redirect}s\n
  time_starttransfer:  %{time_starttransfer}s\n
                     ----------\n
          time_total:  %{time_total}s\n

• Make request

$  curl -w "@responseFormat" -o /dev/null -s "https://www.google.com/"

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