From: "Ara.T.Howard" <ahoward@...>
Date: 2004-08-10T01:41:19+09:00
Subject: Re: ANN: Iowa 0.9 Released

On Mon, 9 Aug 2004, Kirk Haines wrote:

> Iowa could definitely be setup to run directly as an FCGI process, too.  I
> should do that, as an option.  Should be pretty trivial to setup.
>
>> does the mod_ruby or cgi bit manage initially starting the iowa app,
>> or is this a separate step?
>
> The Iowa app runs as a seperate bit.  This allows some flexibility to, for
> example, run the Iowa process on a seperate machine from the web server.
> Down the road I am planning on making it possible to have multiple Iowa
> processes running across multiple machines for load balancing with session
> affinity, so that fits the model of the Iowa process _generally_ being
> seperate, too.

and, of course, the mod_fastcgi module doesa all of this (including session
affinity).

>> so one must avoid doing anything that could potentially block an entire
>> ruby process, like flock, or no new requests would get served - correct?
>
> Hrm.  Yeah.  Interesting point.  I've never had to deal with that problem
> myself, but I can see where it could be troublesome.  One thing I have toyed
> with for about as long as I have been using Iowa is the idea of having as an
> option a forking model instead of a threading model to handle connections.
> With Ruby's all-within-a-process, there would be some potential performance
> advantages to a forking model, especially if it were a forking model with
> preforking.  I just never have done it because I never have needed it.

i'm looking into writing a monitoring app that uses an sqlite backend - it
uses fcntl based locks - so this is a big issue (note to any/all of you using
sqlite as a db for web apps)

> Yep.  The model that I used for webrick was to combine the Iowa and WEBrick
> processes.  So you fire up one process, and it serves regular image/static
> HTML/cgi content through WEBrick's regular capabilities, and Iowa content
> goes through the Iowa side of the process.  It is extremely simple to start
> it up.  Take a look at the examples/webrick part of the release.  You should
> be able to just run examples/webrick/iowa_webrick.rb and everything should
> just work.
>
> Performance also seems pretty decent.  I have not tested it extensively, but
> a few quick tests suggest that for Iowa content it's about 70% of the speed
> of apache + mod_ruby, and I assume most of that is simply the difference in
> speed between WEBrick and Apache.  I'll be doing some more extensive tests
> later with larger & more complex content generation, but that sort of speed
> is pretty reasonable.  On a PIII 800Mhz running Gentoo Linux, that
> translates to something in the low 20s of requests per second for a typical
> moderately sized & moderately complex page.

very slick - i like this approach the best.

> Well, give me a shout if you have any more questions.  I'm always happy to
> give a hand where I can.

will do - thanks for the info

-a
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