From: Rob Hartill <hartill@ooo.lanl.gov>
Message-Id: <9503162116.AA11191@ooo.lanl.gov>
Subject: Re: non-forking again  (NCSA 1.4 approach)
To: new-httpd@hyperreal.com
Date: Thu, 16 Mar 95 14:16:02 MST
In-Reply-To: <199503160735.BAA26199@fiction.isdn.uiuc.edu>;
 from "Brandon Long" at Mar 16, 95 1:35 am
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Brandon Long wrote,

> One other item of note: we don't have multiple children waiting on
> accept, though its been batted around.  I had no idea what it would
> do.  Currently, we use file descriptor passing to pass the accepted 
> socket from the 'root' process to a 'child.'  

The method I prototyped the other day has one child process
doing an accept(*) - so as soon as the connection is made, the
child is ready to go. If the parent does the accept, then it
has to wait on accept, then tell a child (does it have to use
an algorithm here to pick one?) about the connection - this
must surely impact on performance.

My setup has all the serialization being performed before
a call to accept, so a child is always ready for a connection.
As soon as the accept is made, the child sends the parent 
a non-blocking message to tell it that the 'accept' is now history, and
that the next child can 'accept' a connection.

(*) is easily switched to multiple processes 'accepting' - with
no need for a parent to act as a serializer - that I guess should
be a system dependent config setting.


rob