start_epoch vs/or start_time for Firefox-internal metric measurements/calculations?
#165 geöffnet am 11. Dez. 2018
Repository-Metriken
- Stars
- (28 Stars)
- PR-Merge-Metriken
- (PR-Metriken ausstehend)
Beschreibung
Should we use start_epoch or start_time from https://github.com/WPO-Foundation/wptagent/blob/a45466623a8a812cf389c1124d7ff2fd6c4ff8dc/internal/firefox.py#L1061-L1062 and https://github.com/WPO-Foundation/wptagent/blob/a45466623a8a812cf389c1124d7ff2fd6c4ff8dc/internal/firefox.py#L330, respectively?
Or, is sometimes fetchStart/navigationStart[1]?
There are cases where we need to get as close as possible to standard/Chrome timings, but due to other reasons, [2] have to match Raptor/do a one-off calculation**[3]**
[0] [wptagent] https://github.com/WPO-Foundation/wptagent/search?q=fetchStart&unscoped_q=fetchStart
[1] [wptagent] https://github.com/WPO-Foundation/wptagent/search?q=navigationStart&unscoped_q=navigationStart
[2] [custom-metrics] as in trying to calculate DOMContentFlushed from its raw timestamp timeToDomContentFlushed - fetchStart or other non-standard metrics, for which we have to be careful to use the right webpagetest timestamp / W3C * Timing API, etc.
[3] https://github.com/mozilla/wpt-api/issues/97