@@ -39,23 +39,23 @@ This snippet is part of [pagespeed](https://github.com/corewebvitals/pagespeed)
3939
4040 // timing start times are relative
4141 const activationStart = pageNav .activationStart || 0 ;
42- const workerStart = Math .max (pageNav .workerStart - activationStart, activationStart );
43- const dnsStart = Math .max (pageNav .domainLookupStart - activationStart, workerStart );
44- const tcpStart = Math .max (pageNav .connectStart - activationStart, dnsStart );
45- const sslStart = Math .max (pageNav .secureConnectionStart - activationStart, tcpStart );
46- const requestStart = Math .max (pageNav .requestStart - activationStart, sslStart );
47- const responseStart = Math .max (pageNav .responseStart - activationStart, requestStart );
42+ const waitEnd = Math .max (( pageNav .workerStart || pageNav . fetchStart ) - activationStart, 0 );
43+ const dnsStart = Math .max (pageNav .domainLookupStart - activationStart, 0 );
44+ const tcpStart = Math .max (pageNav .connectStart - activationStart, 0 );
45+ const sslStart = Math .max (pageNav .secureConnectionStart - activationStart, 0 );
46+ const tcpEnd = Math .max (pageNav .connectEnd - activationStart, 0 );
47+ const responseStart = Math .max (pageNav .responseStart - activationStart, 0 );
4848
4949 // attribution based on https://www.w3.org/TR/navigation-timing-2/#processing-model
5050 // use associative array to log the results more readable
5151 let attributionArray = [];
52- attributionArray[' Redirect Time ' = {' time in ms' : formatTime (workerStart - activationStart )};
53- attributionArray[' Worker and Cache Time ' = {' time in ms' : formatTime (dnsStart - workerStart )};
54- attributionArray[' DNS Time ' = {' time in ms' : formatTime (tcpStart - dnsStart)};
55- attributionArray[' TCP Time ' = {' time in ms' : formatTime (sslStart - tcpStart)};
56- attributionArray[' SSL Time ' = {' time in ms' : formatTime (requestStart - sslStart)};
57- attributionArray[' Request Time ' = {' time in ms' : formatTime (responseStart - requestStart )};
58- attributionArray[' Total TTFB' = {' time in ms' : formatTime (responseStart - activationStart )};
52+ attributionArray[' Redirect and Waiting duration ' = {' time in ms' : formatTime (waitEnd )};
53+ attributionArray[' Worker and Cache duration ' = {' time in ms' : formatTime (dnsStart - waitEnd )};
54+ attributionArray[' DNS duration ' = {' time in ms' : formatTime (tcpStart - dnsStart)};
55+ attributionArray[' TCP duration ' = {' time in ms' : formatTime (sslStart - tcpStart)};
56+ attributionArray[' SSL duration ' = {' time in ms' : formatTime (tcpEnd - sslStart)};
57+ attributionArray[' Request duration ' = {' time in ms' : formatTime (responseStart - tcpEnd )};
58+ attributionArray[' Total TTFB' = {' time in ms' : formatTime (responseStart)};
5959
6060 // log the results
6161 console .log (' %cTime to First Byte (' + formatTime (responseStart - activationStart)+ ' ms)' ' color: blue; font-weight: bold;'
@@ -71,7 +71,6 @@ This snippet is part of [pagespeed](https://github.com/corewebvitals/pagespeed)
7171})();
7272```
7373
74-
7574## Measure the time to first byte of all the resources loaded
7675
7776#### Snippet
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