Aix process CPU differences.

UNIX AIX
1

Hi,

I'm trying to create a script to catch a process which is consuming high CPU which I have pretty much done but it's just finding the correct place to pull the current CPU for that process.

When viewed in Topas it's consuming 99.*% cpu

But if I try using

ps avg or ps -eo pcpu

it shows as only consuing 9.*%.

is there another command that would reflect the figure in topas?

Thanks,

Matt

2

ps shows the usage over time since start where topas/nmon shows the current usage.

3

Thanks that would explian it then, is there a command that I can use which would show the current CPU consumed?

4

vmstat or sar for example.

5

if you see a process in nmon consuming 99% than that means that it is consuming 99% of one thread (lcpu) what is in most cases not really a reason for concern, particularly not if you i.e. have an oracle DB server
Regards
zxmaus

6

If you have power 5 and higher with micro partition option and lpar uncapped thre is few parameters that you need to check

First you need to check your configuraction

lparstat -i

Check there for Entitled Capacity and Online Virtual CPUs
and MODE

If your Lpars is in mode uncapped nad online virtual cpu value is higher then Entitled Capacity then it mean that you are using over-commitment
Entitled Capacity - means guarantied value of cpu
Online Virtual CPUs means maximum value of cpu your server can use.

You can get in to situation that lpar is using 90% of 0.2 of cpu it is not a problem because it can use max 2CPU and it dues not need it

best commend to make those views would be lparstat 1 10
and vmstat 1 10

for long term analysis i advice nmon or lpar2rdd tool

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