CPU Usage- It is the "amount of time" a CPU was used for processing the given instructions.
Memory Usage- It is the "amount of RAM" was used for processing the given instructions
Entry Processes- It is number of scripts are running at a single time. One entry process take fraction of a second to complete. So in 10 entry process you can have 10-30 visitors.
Number of Processes- It is number of process(script) can run in one time. One process take time till the execution of script.
I/O Usage- It is speed of data transfer between the hard disk and the RAM.
Question: Is high CPU usage bad?
If the CPU usage is around 100%, this means that your computer is trying to do more work than it has the capacity. Always CPU usage must be less than 90%, If so increase the CPU.
