Re: dl() unload / module shutdown issue still unresolved
| From: | Wez Furlong | Date: | Tue, 26 Oct 2004 22:51:46 +0000 |
| Subject: | Re: dl() unload / module shutdown issue still unresolved | ||
| References: | 1 2 3 4 | Groups: | php.internals |
| Request: | Send a blank email to internals+get-13544@lists.php.net to get a copy of this message | ||
Urgh.
On Tue, 26 Oct 2004 15:42:09 -0700 (PDT), Rasmus Lerdorf <rasmus@php.net> wrote:
> It's a bit tricky. When Apache starts up it does a double-pass of the
> conf files in order to do a syntax check. It needs to load all its
> modules in order to do this so our libphp4.so gets loaded which in turn
> causes us to load all our extensions. Then Apache unloads libphp4.so and
> starts over and reloads libphp4.so. Now, in between these two dlopens of
> libphp4.so memory usage can change dramatically. For example, if you have
> a bunch of mod_rewrite rules in your Apache conf the second time
> libphp4.so is loaded it can easily be a page higher in memory. If the
> extensions that PHP loaded on the first pass were not unloaded then any
> callback addresses in the extensions are going to be off by a page and you
> will get some very nasty crashes.
>
> -Rasmus
>