I have a PHP/MySQL web application that gets about 600,000 hits per month. It has been running well for the last few months, but more recently the server is OOMing and crashing. The times between the memory crashes was more rare, but now it has crashed twice in the last two days. When it is running it runs really fast, I just can't keep having the site go down so often.
Does anyone have any ideas on how to fix my problem or have any recommendations on another web host that might fix this problem.
My server setup: Unmanaged VPS (512MB of dedicated memory) It runs CentOS, Apache2, and PHP 5.2. I am only running web applications using PHP and MySQL. My popular application is using cakePHP. I host other sites here, but they do not get many hits. I need to have automated backups.