[wellylug] Re: Running Apache 1.3.x and Apache 2 together (was Re: [wellylug] Setting up PHP on Mandrake 9)

[Grant McLean]

Enkidu wrote:
> OK, I'd also like to know what the differences are between the various
> apache2 versions.

Here's a link with far more than you want to know on the subject:
http://apache.hpi.uni-potsdam.de/document/4_3Multitasking_server.html

The difference essentially comes down to multithreading vs using 
multiple processes (as Apache 1.X does):

> apache2-mpm-worker
   A variable number of processes, each with a fixed number of threads

> apache2-mpm-threadpool
   One main server process with a fixed(?) number of threads

> apache2-mpm-prefork
   Works like Apache 1.x - no threads

> apache2-mpm-perchild
   Multiple server processes each with a variable number of threads
   (never needs to fork in response to load peaks)

It might be argued that with current production Linux kernels, threading
does not offer a significant performance advantage.

I think Apache on Win32 always uses threading.

mod_perl for Apache 2.0 will allow multiple threads in one server 
process to use a pool of Perl engines.  It's still in development, but 
that would probably be simpler and more memory efficient than the 
reverse proxy approach recommended on Apache 1.X.

Cheers
Grant