Module caching in mod_perl

I'm using mod_perl

it seems I have to restart apache every time I modify one of my modules.
is there a way around this so that the modified module will load without restarting apache?

Yep, mod_perl scripts are loaded into memory on apache load, that's why it makes them so much faster.

Use reload instead of restart, its safer

You can also load Apache2::Reload in your conf file to detect changes but it's not 100% perfect and isn't recommended for your production environment

http://perl.apache.org/docs/2.0/api/Apache2/Reload.html

what makes it not 100% perfect and why shouldn't I use it in production environment ?

Its not perfect as different results can happen based on how your perl is installed and how your modules are created. You can hit scenarios where a module you create won't load, or that when you do a change, existing child nodes could report errors before they get replaced by new instances etc.

The main reason why most don't use it in a production environment is simply performance, you are taking a important part of the reason why mod_perl is such kick *** - instead of loading everything in memory once you will be constantly checking %INC for changes and reloading if needed.

Most people I've seen use it in a development environment and after knowing their script is good would upload it to the production machine and use "./httpd reload" to reload all the apache instances.

Give it a try, its ultimately up to you - I would suggest you read this link though

http://perl.apache.org/docs/2.0/api/Apache2/Reload.html