Re: microtime questions

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I just realized that I could check your version, and it appears that we've
found the problem. You're running PHP 4.3.10, so I'd suggest using the non
PHP5 work around on php.net's site.

Cheers!
- Joe


On 4/7/06, Joe Wollard <joe.wollard@xxxxxxxxx> wrote:
>
> Tedd,
>
> The only way that I can even think of this as being possible is if you
> call microtime() instead of microtime(true). The former will return 'msec
> sec' separated by a space which can produce a negative number because you've
> essentially got two different types of measurements there. IMHO PHP should
> probably throw out an error when two strings are used in a mathematical way
> - in this case (without the TRUE arg) here is a possible equation that could
> be evaluated.
>
>   0.15290800 1144430717
> - 0.86641600 1144430716
>
> PHP evaluates this to -0.713508 (or 0.15290800 - 0.86641600) It's negative
> because we're not talking about msecs from the same second - it ignores the
> seconds and only pays attention to the microseconds. So if you're using
> microtime(true) how can this happen on your machine? Well, off the top of my
> head I think you should verify that your machine (or your hosting service)
> is running PHP5 || >. IF not, and error reporting is turned off, then you'll
> get a negative number from time to time since the seconds are being ignored.
>
>
> http://php.net/microtime has an example of how to emulate microtime(true)
> on PHP < 5
>
> Hope that helps!
> -Joe
>
>
> On 4/7/06, Brad Bonkoski <bbonkoski@xxxxxxxxxxxxxx> wrote:
> >
> > How is the CPU not in question?  Does this script run on air?
> > It may not be YOUR CPU, but it is still a CPU bound by the sceduling
> > algorithm of the Operating System, so the time differentials are too be
> > expected.
> > -B
> >
> > tedd wrote:
> >
> > > At 12:24 PM -0400 4/7/06, Brad Bonkoski wrote:
> > >
> > >> Interesting...
> > >> as for your first question...
> > >> Know that PHP/Apache does not have free reign to your CPU, so the
> > >> times could be different based on the scheduling going on in the OS
> > >> kernel.
> > >>
> > >> As for the second one...
> > >> No idea why you would get a negative number, I just copied and ran
> > >> from the command line and did not encounter 1 negative time for about
> > >> 30 runs....
> > >>
> > >> Do you get negative times if you run it from the command line as
> > well?
> > >> -B
> > >>
> > >>> RE:
> > >>>
> > >>> http://www.xn--ovg.com/microtime.php
> > >>>
> > >
> > > Brad:
> > >
> > > Thanks for looking.
> > >
> > > My questions are with regard to what happens on the site, not via my
> > > command line. As such, my command line and my CPU are not involved.
> > >
> > > Can you answer the questions as they pertain to the site in question?
> > >
> > > Thanks.
> > >
> > > tedd
> > >
> >
> > --
> > PHP General Mailing List (http://www.php.net/)
> > To unsubscribe, visit: http://www.php.net/unsub.php
> >
> >
>

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