From: Sean Chittenden <sean@...>
Date: 2002-10-09T10:23:46+09:00
Subject: Re: mod_ruby post-request cleanup

[moving to modruby@modruby.net, remove ruby-talk from the address on reply]

> I'm trying to keep a pool of database connections persistent across
> requests.
> 
> I'm doing this via a class variable containing an hash of
> datasources that are known about.  Each hash entry contains an array
> of connections (which are intended to be reused across requests).
> This actually all sits inside another class, that handles the
> determination of what datasources are loaded up, based on an XML
> configuration file, in case that's important.

Nope, shouldn't be.

> Somehow, the hash seems to be losing the keys from session to
> session, meaning I'm re-connecting to the database all the time.  As
> I say, this feels like some kind of silly bug, but ...

Try using a global variable instead of a class variable.  Are you
using apache/reload.rb?  If you reload the class, the old class's
class variables should get nuked.

> Just after sending the page back, via CGI.out(), I'm printing out
> what keys are in the hash, and I can see the one I expect.  However,
> at the start of the next request, while the class variable still
> exists (and has the same address), the keys seem to be gone.

This smells like it could be bugish... I wonder if the hash is being
marked with rb_gc_mark() instead of rb_gc_mark_children().  I wouldn't
call this a bug quite yet, but it could be.

> As I say, it's probably just a bug, but I figured I should check
> whether mod_ruby does some kind of cleanup of non-class variables at
> the end of each request, that I might be falling foul of.

Nothing specifically for non-class variables that are outside of
normal scope rules.

> I'm going to do some tests with something simpler, but I'd prefer to
> save myself some messing about if there's something mod_ruby is
> doing that I don't know about.

It's possible.  -sc

-- 
Sean Chittenden