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Date: Thu, 30 Oct 2008 07:38:30 +0100
From: Mladen Turk <mturk@apache.org>
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To: dev@httpd.apache.org
Subject: Re: MPMs, COW vs Child Process Spawning
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Paul Querna wrote:
> Is COW ability of fork important enough with modern memory and operating 
> systems, to maintain two significantly different code paths for spawning 
> children processes?
> 
> Background:
> 
> One of the things I would like to do on the Simple MPM is unify how 
> child processes are created on win32 and unix.
> 
> On Win32, there is no fork, so roughly speaking what the current winnt 
> MPM creates a new process, and feeds the configuration over a pipe to 
> the new child.
> 
> On Unix, all of the current MPMs use fork, and do not execute a new 
> process, but instead then drop privileges and continue running.
> 
> What I would like to do, is change Unix to use the same pattern as on 
> Windows.
> 

I'm currently working on a portable apr process shared data
using shared memory (See apr-dev list about the proposal)
http://mail-archives.apache.org/mod_mbox/apr-dev/200804.mbox/%3C4809F5F9.4060006@apache.org%3E
(Didn't get any replies to that, so it's either OK to proceed
  or it was totally non understandable ;)

This could help unifying the platforms that need some sort of
passing data between parent and child(s)


Regards
-- 
^(TM)