Hi,
I've been catching up on the modperl list archives, and would
just like to recommend "mathopd" as an image web server.
After having difficulties with the sheer number of front end
apache processes necessary to handle 10 backend modperls,
(difficulties: high load average and load spikes, kernel time
wasted scheduling lots of httpds, higher than expected latency
on simple requests), I switched all images to another IP
address on the same box (extending their IMG SRC somewhat
obviously), but now served by mathopd.
Mathopd is a simple select based, http 1.1 (keep alive)
compliant tiny webserver that is very configurable. I was
doubtful that it would hold up (it comes with zero documentation ..
the docs say "read the source"). But it has not crashed *once*,
and its very nice to see just one 22mb process with 500+ minutes
of cpu time (for several weeks of work), and have images
come in fast and reliably.
It uses select and as many file handles for a proc as you have.
If load increases beyond (say) your limit of 1024 fds, it re-uses
currently unused but kept-alive fds, meaning a graceful
degradation. It is also exceedingly fast, much faster than
apache serving images (that doesnt matter, but it does mean
its frugal with your CPU).
Of course I still have 120+ apache httpds (now just being front
end for *page* requests), and my wish is that mathopd would add
proxy and regexp rewrite capability, then I could do away with
apache completely on the front end !! or I guess apache2 with
mod_rewrite and mod_proxy would solve that, at the risk of
thread related teething problems.
Just a recommendation from left field.
-Justin