Introduction to the Apache Web Server - ApacheCon

• Some modules, like mod php, don’t work very well in a threaded environment, and so you need to stick
with prefork if you’re using php.
• Of course, some modules just don’t work at all on 2.0 yet, and in that case you have to stick with 1.3
perchild
http://httpd.apache.org/docs-2.0/mod/perchild.html
Parent
process
...
Threaded child processes
• Does not work yet
• Multi-process, multi-threaded
• Allows configuring things per child process
In a nutshell, here’s what perchild does, and why it is cool:
perchild lets you configure Apache per child. Hence the name. In other words, you can actually have a
different configuration for each Apache child process.
This allows you to run virtual hosts as a particular user (as opposed to just the cgi programs, like suexec lets
you do). It lets you configure one vhost to run 10 threads, and another to run 200 threads. To specifically
assign a particular child process to a particular vhost. And so on. It is very cool. But we should probably
quit talking about it, since it is largely imaginary, and likely to remain so for some time.
win32
Parent
Threaded
Child
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