Some sort of rounding error, yes. The internal representation (before converting the value to float) is microseconds. Actual precision depends on the operating system, as the comment in time.h says:
// Returns a platform-dependent high-resolution tick count. Implementation > // is hardware dependent and may or may not return sub-millisecond > // resolution. THIS CALL IS GENERALLY MUCH MORE EXPENSIVE THAN Now() AND > // SHOULD ONLY BE USED WHEN IT IS REALLY NEEDED. Also, note that V8 itself doesn't know about "performance.now()". It is up to embedders to provide this functionality -- Chromium has an implementation, d8 has its own (which is what I'm talking about above), I don't know about node.js. On Wed, Feb 1, 2017 at 10:08 AM, Brian Hicks <[email protected]> wrote: > The spec for performance.now says that the resulting values should be > accurate to the thousandth of a millisecond. In my testing, I'm getting > values even more precise than that, down to the ten trillionth place (13 > digits past the decimal) > > So my question: is it safe to rely on the values beyond the thousandth > place, or is this some sort of rounding error or measurement noise? > > -- > -- > v8-users mailing list > [email protected] > http://groups.google.com/group/v8-users > --- > You received this message because you are subscribed to the Google Groups > "v8-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
