SAR (Cpu)

To monitor CPU usage

# sar -u 10 5

The o/p has the following columns.

%usr - Percent of CPU running in user mode (executing user code).
%sys - Percent of CPU running in system mode (executing OS code).
%wio - Percent of CPU running idle with a process waiting for block I/O.
%idle - Percent of CPU that is idle.

Inference

• A low %idle indicates CPU intensive job.
• A high %wio indicates a disk contention.
• A high %sys (>20) indicates a bottleneck. May be due to swapping or paging.
• A high %usr indicates applications not tuned properly or over utilization of CPU.

Thanks