curl -so /dev/null https://bing.com -w 'time_namelookup:  %{time_namelookup}\n time_connect:  %{time_connect}\n time_appconnect:  %{time_appconnect}\n time_redirect:  %{time_redirect}\n time_pretransfer:  %{time_pretransfer}\n time_starttransfer:  %{time_starttransfer}\n ----------\n time_total:  %{time_total}\n'

#返回结果

 time_namelookup:  0.033131
 time_connect:  0.141500
 time_appconnect:  0.282717
 time_redirect:  0.000000
 time_pretransfer:  0.282813
 time_starttransfer:  0.409545
 ----------
 time_total:  0.409645