Discrepancy btw TTFB in main html request and WPT table

Web Performance Discuss Test Results
1

I am finding big discrepancy btw First byte time that is reported, and TTFB that i see in request -
e.g., First byte time here is rather unusually high here - 1.37 sec
but, time shown in request is,

Request Details

Resource Content Type Start Offset DNS Lookup Initial Connection SSL Negotiation Time to First Byte Content Download Bytes Downloaded Error/Status Code IP

1 https://www5.v1host…nu=MyHomeSummaryPage text/html 0.498 s 0 ms 20 ms 106 ms 181 ms

0.498 s + 20ms + 106ms + 181 ms adds to - 805 ms much lower than 1.37 sec.

In addition, startOffset - (InitialConnection+SSL) is > 0, and here it is 374 ms - Generally, this value should be close to zero, right?

This one is repeatview numbers - not sure if that affects anything – One possibility here is that starttime of test can be non-zero for repeat view, and then we have to subtract this initial offset from reported numbers to get actual numbers?

2

Do you have a link to the test result? The page-level TTFB includes everything from the start until something comes back (including redirects). In the case of repeat view it may be getting thrown off if for some reason the main resource is being served from cache.

3

okay, i sent you link to the test result separately.

4