Bug 84914 - [Chromium] Need to expose TimeTicks::HighResNow()
Summary: [Chromium] Need to expose TimeTicks::HighResNow()
Status: RESOLVED WONTFIX
Alias: None
Product: WebKit
Classification: Unclassified
Component: New Bugs (show other bugs)
Version: 528+ (Nightly build)
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords: Performance
Depends on:
Blocks:
 
Reported: 2012-04-25 17:42 PDT by James Simonsen
Modified: 2013-04-15 07:14 PDT (History)
5 users (show)

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Description James Simonsen 2012-04-25 17:42:41 PDT 
In order to properly implement window.performance.now(), we need a sub-millisecond timer. Currently, we return TimeTicks::Now(). On Windows, that only has (at best) a 1 ms resolution. We need to instead use TimeTicks::HighResNow() to get microsecond resolution. Note the warnings in time_win.cc that HighResNow() is slower and not always available. For some users, they'll never get better that tick resolution (1 - 15 ms).

This should probably be plumbed through via monotonicallyIncreasingTime().

We should also be careful to ensure that TimeTicks::Now() and TimeTicks::HighResNow() use the same time base. The network times that are used for Navigation Timing are passed in by calling TimeTicks::Now() in the browser process.