I have noticed a that a serious memory leak is occuring with PHP when using the ob_gzhandler. It is noticable very quickly after starting Apache and reloading a few pages, the process size goes up dramatically - much more than if PHP is configured NOT to use the ob_gzhandler, which is I think when the Zend optimizer caches pages. Merely having support compiled in does not cause the effect.

I have mod_ssl configured with:

--with-layout=Del --with-apache=../apache --with-ssl=../openssl --with-mm=../mm --activate-module=src/modules/php4/libphp4.a --activate-module=src/modules/extra/mod_gzip.c

PHP compiled with:

--with-apache=../apache --enable-trans-sid --with-my-sql --with-zlib --with-mcrypt

And then Apache is made with those options that mod_ssl configures it with. Using Zend optimizer 1.0.0 for PHP4.0.4.

Despite the numerous different modules that are compiled into Apache, I feel it is with the ob_gzhandler that the problem lies as deactivating it seems to make the problem go away.