In AX, topas can be used to monitor CPU usage of the system. Topas is similar to top in Linux though both are not the same.

Question : How to monitor CPU usage in AIX?
Answer : ps command can be used to report a snapshot of the current processes in AIX. Use option aux and sort based on the column to get the top usage based on the parameter you need. If you need to get CPU then you will need to sort column 3.
Example :

[root@server ~]# while true;do echo `ps aux |head -1`;ps aux |sort -nrk 3| head -10;sleep 2;clear;done

Note : Above command will output top 10 processes with highest %CPU in an interval of 2 seconds. Press "Crtl C" to exit the while loop.


Question : How to monitor CPU usage in AIX?
Answer : Besides using method above, topas command can be used to monitor %CPU in AIX.
Example :

[root@server ~]# topas [root@server ~]# topas -P <--- To display full screen of processes

Question : How to monitor CPU usage in AIX?
Answer : sar command can be used to monitor %CPU in AIX. Use sar with option "u" and specific the interval and numintervals needed.
Example :

[root@server ~]# sar -u 3 3

Note : Above command with execute sar -u in an interval of 3 seconds for 3 times.