Magento 1.9.1 php-fpm High CPU Usage but Low Memory Usage

I am running 2 pretty standard Magento websites in a cloud with 16 vCPU and 16 vRAM. But today i found out that my sites are running horribly slow with almost 100% vCPU all the time, but only 10% RAM. I couldn't figure out what the problem is and no idea where to check first. Please help guys, thank you.