Navigation Timing

WebPageTest Private Instances
1

From what I can tell, WPT doesn’t currently track all timing metrics. The ones that are being tracked are apparently calculations derived probably from the two primary missing ones (navigation/fetchStart). Ideally all numbers the browser provides in window.performance.timing.

Here’s the ones that I can’t find:
navigationStart
fetchStart

These others would be helpful for completeness
unloadEventStart
unloadEventEnd
redirectStart
redirectEnd
fetchStart
domainLookupStart
domainLookupEnd
connectStart
connectEnd
secureConnectionStart
requestStart
responseStart
responseEnd
domLoading
domInteractive
domComplete
secureConnectionStart

2

WebPagetest doesn’t rely on window.performance for it’s measurements so “navigationStart” doesn’t really mean anything - that is the zero-time as far as WPT is concerned.

Are there specific time measurements that you’re looking for that aren’t currently exposed (not point-in-time marks, but durations)?

3

First question, how do you determine domContentLoaded and LoadEvent without navigationStart? Those measurements under that name wouldn’t be correct without using navigationStart as the comparison.

I’m looking for marks rather than measurements. I’m compiling data from multiple tools WPT, Chrome Telemetry, phantomas. Since WPT doesn’t use the Navigation Timing API for measurements, these comparison are difficult to make.