Re: [ANN] LuaProfiler 2.0
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- Subject: Re: [ANN] LuaProfiler 2.0
- From: Glenn Maynard <glenn@...>
- Date: 2005年6月15日 15:01:33 -0400
On Wed, Jun 15, 2005 at 02:54:23PM -0400, Aaron Brown wrote:
> Glenn Maynard wrote:
>
> > However, all of this goes away if you avoid floating-point
> > entirely.
>
> And use 64-bit ints instead? (Or bignums?)
Yep. Integers are much more easily predictable than floating-point: no
control word to enable unexpected exceptions, change the rounding
order or precision, no loss of precision due to unexpectedly large
values, results are predictable to the bit--they're much better suited
to measuring fine timings than floating point.
(Of course, not all systems have 64-bit ints, but not all systems
have doubles, either. Since this is inherently x86-specific, nonportable
code, that's not much of an issue. For portable code, I usually use
one 32-bit int for seconds, and one for micro- or nanoseconds.)
--
Glenn Maynard