Monitoring Processor Use
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Monitoring Processor Use
To determine process utilization, you should gather CPU statistics. You should also
monitor system scalability by adding users and increasing the system workload.
Use utilities such as sar (System Activity Reporter) and mpstat to monitor process
use.

Using the sar Utility (AIX, HP-UX, Intel Solaris)

You can use sar to sample cumulative activity counters in the operating system at
specified intervals.

Report CPU Utilization

To determine process use, use the following sar command:
$ sar -u 5 5
:
This command samples CPU usage five times, in five second intervals, as shown
below:
$ sar -u 5 5
15:30:25 %usr %sys %wio %idle
15:30:30 49 36 0 14
15:30:35 52 41 0 7
15:30:40 46 45 0 8
15:30:45 46 44 0 10
15:30:50 50 41 0 9
Average 46 41 0 9
The statistics above show that the CPU was only 9% idle for the given time interval.
If your performance criteria specify that CPU usage must be below a certain
percentage, you can use sar to sample usage at a chosen interval during peak load
times.