If you think of the number in terms of percentage utilization, 1.0 represents 100% of a single CPU core. The decimal represents the amount of active tasks requesting CPU resources to perform an action. If the third number is too high, you’ve got a problem to deal with. Using these 3 measurements you can get a sense of whether a spike was a short term occurrence or if it’s a prolonged event. The third and final number is the average load over a 15 minute period. The second decimal is the average load over a 5 minute period. The first decimal represents the average CPU load over the past minute. Under Linux, CPU usage is reported as a series of three decimals like the following result of the ‘uptime’ command: If you’re used to Windows style CPU reporting which shows you a percentage based statistic of utilization, Linux load reporting can be a little confusing. Properly allocating the cores to run the most VM’s efficiently is the goal of any virtualized system. 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. It’s recommended that your VM CPU allocation match up with a physical CPU core. When you create a new virtual machine, the VM requires at least 1 CPU core to operate. More often it’s the CPU causing resource shortages, especially if you operate a virtualized environment. These days, RAM and storage are cheap and plentiful.

CPU load is one of the most important metrics for measuring hardware usage. Under utilization can show you opportunities to use hardware more efficiently. Gradual increases over time can help you predict hardware growth requirements.

Unexpected spikes in resource usage can indicate a software or hardware problem. Monitoring, anticipating, and reacting to server load is a full time job in some organizations.

Centos check cpu usage