From: rst@ai.mit.edu (Robert S. Thau)
Date: Sun, 23 Apr 95 17:23:43 EDT
Message-Id: <9504232123.AA05324@volterra>
To: new-httpd@hyperreal.com
Subject: Re: fork free
Sender: owner-new-httpd@apache.org
Precedence: bulk
Reply-To: new-httpd@apache.org

I agree with this analysis for the moment.  The only thing that gives me
pause about it is that it may not be adequate for HTTP/1.1 (specifically,
for persistent connections).  The most straightforward way to implement
these HTTP/1.1 keep-alives would be to allocate one member of the server
pool to each client for the duration of its connection --- but this does
mean that each client will be locking up a whole server process for a 
nontrivial amount of time (perhaps more than a minute for retrievals of     
pages with a *lot* of inlines --- latex2html output with gif-ized math,
and Ellen Spertus' non-profit orgs page with 60-odd logos, both come to
mind from around here).

On the other hand, allocating a separate process for each such long-lived
connection might not be easy on swap space.

What would be best, if we can manage it, would be to somehow distribute
the individual requests coming in from a kept-alive connection around the
server pool... but that won't be easy (at least, not without creating an
NCSA-1.4-style bottleneck distributor process).

rst