I’m currently managing a Joomla 5 site and I’ve run into a performance hurdle that I can't quite figure out. Lately, whenever I try to run more intensive background tasks or automation scripts to test site stress levels, the entire backend becomes sluggish or hits me with a "Request Timeout."

The site works perfectly fine under normal traffic, but the moment I use a tool to execute more complex scripts in a free way to simulate user interactions, the server load spikes and the admin panel becomes almost unusable. I've already tried increasing my PHP memory_limit to 512MB and bumped up the max_execution_time, but it feels like there’s a bottleneck elsewhere.

I’m starting to wonder if this is related to how Joomla handles session locking during heavy script execution, or if there's a specific system plugin that might be over-scanning these background requests and causing a loop. Has anyone else experienced their backend crashing or slowing down when running external automation?

Are there specific database optimization settings or caching layers you’d recommend to keep the administrator interface responsive even when the system is under heavy load from these scripts? I’d love to hear if anyone has a "best practice" configuration for keeping the site stable during high-concurrency testing.

Thanks for the help!