Gah.
I botched that, I didn't reset the timer.
Total Time: 00:00:03.08 //str_replace
Total Time: 00:00:04.32 //preg_replace
Total Time: 00:00:03.05 //str_replace
Total Time: 00:00:03.67 //preg_replace
Total Time: 00:00:03.27 //str_replace
Total Time: 00:00:04.40 //preg_replace
Closer than I thought. Probably deserves a better comparison tho. From these
results I'll probably stop yelling at people for using preg_replace when
str_replace will do.
Regards
Stephen Thorne.
On Thu, 30 Jan 2003 08:50, Stephen Thorne wrote:
> On Thu, 30 Jan 2003 06:48, Ilia A. wrote:
> > > I may be wrong since I haven't profiled this, but my understanding is
> > > that str_replace is much faster than doing either of the regex
> > > replacements. For that reason alone, there is a use for it.
> >
> > Normally it would be quite faster, however once case sensitivity is added
> > to the mix I believe the speed difference would be minimal. I've done
> > some benchmarks and the speed difference between str_replace() and
> > preg_replace() is only about 1/2 second in across 100000 executions (5
> > replaces per instance). Another .6 of a second is added when
> > preg_replace() is used with 'i' flag which makes it case insensitive. I
> > have not benchmarked the stri_replace code but I imagine it would be in
> > the same ballpark, meaning that we are adding a fairly large chunk of
> > code for performance benefit of a 1 microsecond (1 millionth of a second)
> > per instance.
> >
> > Ilia
>
> Lies, damn lies and statistics.
>
> You say the difference is only 1/2 second accross 100000 executions, but
> that means nothing unless you put it in context of how long the 100000
> executions took. 1/2 second could mean 90% difference or 1% differene.
>
> I wrote a very unscientific script to do a simple benchmark
>
> <?php
> include('stopwatch.inc');
> $SW = new StopWatch;
> for ($i=0;$i<500000;$i++)
> str_replace('abcdefgh', 'def',
> 'fkjdals;fjdsakl;fjdsakl;fjdskl;fadabcdefghfdsafdsafdsa');
> $SW->Stop();
>
> for ($i=0;$i<500000;$i++)
> preg_replace('/abcdefgh/', 'def',
> 'fkjdals;fjdsakl;fjdsakl;fjdskl;fadabcdefghfdsafdsafdsa');
> $SW->Stop();
> ?>
>
> I did quite a few runs and picked the upper and lower end of the results to
> paste here
>
> Biggest difference
> Total Time: 00:00:03.00
> Total Time: 00:00:08.90
>
> Smallest difference
> Total Time: 00:00:03.12
> Total Time: 00:00:06.94
>
> Bearing in mind this is on a pre-working-hours quad hyperthreaded 1.4ghz
> xeon box. So I've got a cpu just about all to myself here.
>
> Regards,
> Stephen Thorne.
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