mod_perl spawning multiple Handler requests for a single browser request

[Daniel Walmsley]

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Hi all, I am having trouble with mod_perl, and I must confess to not
being terribly experienced with its inner workings so please bear with me.

I have a URL which is accessed by a GET request, and processes an image.
This can take a while to complete. What seems to be happening _some_ of
the time is that mod_perl decides after about 20-30 seconds to send the
_same_ request to another process, which results in our software
attempting to process the image twice. It doesn't stop the original
process - that one completes successfully. The second one throws up an
error because it can tell that the image has already been modified.

I've done a few google searches, and searches on perl.apache.org, and
nothing has turned up that seems to work. I've tried using
$r->kill_alarms() before the critical/time-consuming piece of code, but
I'm not entirely sure that that is what it's intended for.

In short, my question is this:
- - why does mod_perl appear to be dispatching the same request twice for
a single web request?
- - and what can I do to stop it?

I'm using mod_perl 1.26-3.0woody1 with apache 1.3.26-0woody3 and perl
5.6.1-8.3 on Debian Stable.

If anyone could help, that would be great.

Regards,
Dan
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