[Python-Dev] Drop the new time.wallclock() function?

[Matt Joiner]

+1. I now prefer time.monotonic(), no flags. It attempts to be as high
precision as possible and guarantees never to jump backwards. Russell's
comment is right, the only steady sources are from hardware, and these are
too equipment and operating system specific. (For this call anyway).
On Mar 16, 2012 3:23 AM, "Russell E. Owen" <rowen at uw.edu> wrote:

> In article
> <EFE3877620384242A686D52278B7CCD3362609 at RKV-IT-EXCH104.ccp.ad.local>,
>  Kristján Valur Jónsson <kristjan at ccpgames.com> wrote:
>
> > What does "jumping forward" mean?  That's what happens with every clock
> at
> > every time quantum.  The only effect here is that this clock will be
> slightly
> > noisy, i.e. its precision becomes worse.  On average it is still correct.
> > Look at the use cases for this function
> > 1) to enable timeouts for certaing operations, like acquiring locks:
> >       Jumping backwards is bad, because that may cause infinite wait
> time.  But
> > jumping forwards is ok, it may just mean that your lock times out a bit
> early
> > 2) performance measurements:
> >       If you are running on a platform with a broken runtime clock, you
> are not
> > likely to be running performance measurements.
> >
> > Really, I urge you to skip the "strict" keyword.  It just adds confusion.
> > Instead, lets just give the best monotonic clock we can do which doesn"t
> move
> > backwards.
> > Let's just provide a "practical" real time clock with high resolution
> that is
> > appropriate for providing timeout functionality and so won't jump
> backwards
> > for the next 20 years.  Let's simply point out to people that it may not
> be
> > appropriate for high precision timings on old and obsolete hardware and
> be
> > done with it.
>
> I agree. I prefer the name time.monotonic with no flags. It will suit
> most use cases. I think supplying truly steady time is a low level
> hardware function (e.g. buy a GPS timer card) with a driver.
>
> -- Russell
>
>
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