Based on a gist https://gist.github.com/sandeepraju/1f5fbdbdd89551ba7925abe2645f92b5 by https://github.com/sandeepraju
Modified by jay@gooby.org, @jaygooby
Usage: ttfb [options] url [url...]
-d debug
-l <log file> (infers -d)
-n number of times to test
Examples:
$ ttfb example.com
DNS lookup: 0.523402 TLS handshake: 0.000000 TTFB including connection: 692724 TTFB: .692724 Total time: 0.693508
$ ttfb -n 5 example.com
min .203970 max .181486 median .190033
$ ttfb -n 5 bbc.co.uk news.bbc.co.uk
bbc.co.uk min .032791 max .039401 median .029214
news.bbc.co.uk min .032927 max .032237 median .037458
$ ttfb bbc.co.uk news.bbc.co.uk
bbc.co.uk DNS lookup: 0.005291 TLS handshake: 0.089403 TTFB including nnection: 0.119651 TTFB: .030248 Total time: 0.506010
news.bbc.co.uk DNS lookup: 0.004266 TLS handshake: 0.077179 TTFB including nnection: 0.110649 TTFB: .033470 Total time: 0.598472
Implicitly follows redirects using curl's -L
Log all response headers (default log file is curl.log) by calling with -d
Override the default log file by specifying -l /some/file
Get min, max and median values by specifying the number of times to call
the URL (-n2 etc)
If you specify more than one url and have specified -d or -l the log file
will be prefixed with the URL being requested.
$ ttfb -d bbc.co.uk news.bbc.co.uk
bbc.co.uk DNS lookup: 0.005309 TLS handshake: 0.074216 TTFB including connection: 0.106453 TTFB: .032237 Total time: 0.462894
news.bbc.co.uk DNS lookup: 0.005355 TLS handshake: 5.358041 TTFB including connection: 5.397377 TTFB: .039336 Total time: 6.013918
$ ls
bbc_co_uk-curl.log news_bbc_co_uk-curl.log
See https://blog.cloudflare.com/a-question-of-timing/ and https://curl.haxx.se/docs/manpage.html for an explanation of how the curl variables relate to the various stages of the transfer.
To get a better approximation of devtool's TTFB, consider
the time without the connection overhead:
%{time_starttransfer} - %{time_appconnect}
Uses a dirty eval to do the ttfb arithmetic. Depends
on bc and column commands.