Re: Re: [ZEND-ENGINE-CVS] cvs: ZendEngine2 / zend_execute.c
| From: | Sterling Hughes | Date: | Fri, 16 Jul 2004 16:35:32 +0000 |
| Subject: | Re: Re: [ZEND-ENGINE-CVS] cvs: ZendEngine2 / zend_execute.c | ||
| References: | 1 2 3 4 | Groups: | php.internals php.zend-engine.cvs |
| Request: | Send a blank email to internals+get-11293@lists.php.net to get a copy of this message | ||
can we put that in the release notes - "php is like 50% more stable,
it takes 20 seconds not 10 to crash it?"
-sterling
On Fri, 16 Jul 2004 12:15:46 -0400, Ilia Alshanetsky <ilia@prohost.org> wrote:
> On July 16, 2004 11:58 am, Thies C. Arntzen wrote:
> > hey ilia,
> >
> > here's another one of my meaningess, synthetic benchmarks (this is how
> > the CreatorsOfPHP(tm) would call them)
> >
> > ackermann(8) (source on request - highly recursive)
>
> Recursive functions in PHP are inherently dangerous as without proper limits
> they will rather quickly ~5671 iterations with a basic function a() { a(); }
> (PHP 4/5).
> By comparison the same code only takes 2897 iterations before the patch. While
> the patch does not solve this crash it reduces it's chances by nearly 50%
> (unexpected benefit).
>
> More over the crash problem that the patch solves is not theoretical that I
> made up because I have nothing better to do. We have at least 2 confirmed bug
> reports by different people and surely there are others who came across this
> issue and didn't report it.
>
> Yes, you are correct, with a dedicated benchmark specifically designed to
> "exploit" the allocation routine change there is a performance drop, but
> surely stability is more important then speed. If that is not that case,
> there are a whole lot of optimizations we can perform, but that'd mean users
> will need to write their code extra carefully :-), which as we know is not
> going to happen.
>
> Ilia
>
>
>
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