Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 04-08-2006 Installation Manual page 774

Instead of only forking child processes, the worker MPM serves requests by using
threads with server processes. The preforked child processes are multithreaded. This
approach makes Apache perform better by consuming fewer system resources than the
prefork MPM.
One major disadvantage is the stability of the worker MPM: if a thread becomes corrupt,
all threads of a process can be affected. In the worst case, this may result in a server
crash. Especially when using the Common Gateway Interface (CGI) with Apache under
heavy load, internal server errors might occur due to threads unable to communicate
with system resources. Another argument against using the worker MPM with Apache
is that not all available Apache modules are thread-safe and thus cannot be used in
conjunction with the worker MPM.
WARNING: Using PHP Modules with MPMs
Not all available PHP modules are thread-safe. Using the worker MPM with
mod_php is strongly discouraged.
41.4.5 External Modules
Find a list of all external modules shipped with SUSE Linux Enterprise Server here.
Find the module's documentation in the listed directory.
FastCGI
FastCGI is a language-independent, scalable, and open extension to CGI that pro-
vides high performance without the limitations of server-specific APIs. FastCGI
applications are very fast because they are persistent. There is no per-request start-
up and initialization overhead.
Package Name: apache2-mod_fastcgi
Configuration File: /etc/apache2/conf.d/mod_fastcgi.conf
More Information: /usr/share/doc/packages/apache2-mod_fastcgi
mod_perl
mod_perl enables you to run Perl scripts in an embedded interpreter. The persistent
interpreter embedded in the server avoids the overhead of starting an external inter-
preter and the penalty of Perl start-up time.
Package Name: apache2-mod_perl
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