Shell Programming and Scripting

I am trying to find the total CPU usage on an IBM AIX machine that could have several processors. I am using
ps uax | awk {'print $3'} to find the CPU usage columns for the processes and then adding them up to find the total CPU usage. It was doing fine. However to my surprise, I find that the %CPU usage column shows a much higher value (38601304.034456). I must tell that interestingly only the first 3 processes (java ant command, some dba command and the other one admin command from root) are showing these values and rest are cool. I was of the opinion that the %CPU usage would never cross 100. I am working for a load manager and need to find the total %CPU usage on several boxes and selects the most lightly loaded one for a request to be redirected.

Is there anything seriously wrong in my approach? Can someone throw some light?

Thanks

Asutoshc

I wouldn't use ps to monitor cpu performance like that. Try other commands like vmstat. This link should be helpful.

http://publib.boulder.ibm.com/infoce...v5r3/index.jsp

Stupid IBM website - the link just goes to the main page instead of the page I was looking at when I pasted the link in.

Once you're there on the left panel click on Performance Management and Tuning, then the first book "Performance Management Guide". There is a whole chapter on CPU performance monitoring.

nmon is also very nice on AIX:

http://www-128.ibm.com/developerwork...aix/index.html