Monitoring, anticipating, and reacting to server load is a full time job in some organizations. Unexpected spikes in resource usage can indicate a software or hardware problem. Gradual increases over time can help you predict hardware growth requirements. Under utilization can show you opportunities to use hardware more efficiently. CPU load is one of the most important metrics for measuring hardware usage.
These days, RAM and storage are cheap and plentiful. More often it’s the CPU causing resource shortages, especially if you operate a virtualized environment. When you create a new virtual machine, the VM requires at least 1 CPU core to operate. It’s recommended that your VM CPU allocation match up with a physical CPU core. That means your host server can only run as many virtual machines as it has cores (minus 1 for the host server), and usually a VM needs more than 1 core if it’s doing any real work. Properly allocating the cores to run the most VM’s efficiently is the goal of any virtualized system.
Read more at IT World.