I've hosted a php application built on top of symfony 1.4 on a dedicated server. The server (apache on Redhat) has a 4 core cpu, 32GB ram & a SSD. In the application there is a php script (symfony task) that runs once a month and that task is heavy (it takes like 30 minutes to complete and it executes lots of mysql queries on the application's database). I observed that the response time increases significantly when the task is run. It gets worse when concurrency level is also high at the same time. max-memory-limit in php.ini is set to 4096MB now.
Is there a way to run the task without reducing the response time of concurrent request? It doesn't matter if the task take more time without affecting the response time. A hardware based solution, configuration based solution or architecture level solution is ok.