When you issue one of these commands "w, top, or uptime", you would find a parameter called Load Average with 3 fields; I thought it has sth related to a CPU utilization but after got asked about it in a Google interview, it seems to have more than that.
For multiple CPUs architecture, it means that this number of processes can be scheduled on these CPUs.
Here is uptime output:
14:34:03 up 10:43, 4 users, load average: 0.06, 1.11, 0.09
14:34:03 up 10:43, 4 users, load average: 0.06, 1.11, 0.09
This means that the CPU is 6% underloaded in the last minute and overloaded by 11% in the last 5 minutes and is underloaded with 9% in the last 15 minutes.
For multiple CPUs architecture, it means that this number of processes can be scheduled on these CPUs.
This is useful for capacity planning and performance monitoring of CPU and the running processes.
It has been considered that 3 is a good threshold value (From O'Reilly UNIX Power Tools) .
