Overall CPU Usage

Hi Guys,

I am a newbie on the forum. This is my first post, so first of all I would like to introduce myself.

I am a SAS Analyst programmer working for an Health Insurance client. SAS is installed on a 16 CPU AIX Server with partitions running with shared processor. I have couple of questions hope you all will answer patiently :smiley:

  1. First of all I have no clue of what does this 16 CPU AIX Server with partitions running with shared processor means??
  • I ran the below command and after going through some definition created this statement.
  • vmstat -w 1 2, attached is the result (cmd_1)

So what exactly this 16 CPU AIX Server with partitions running with shared processor means??

  1. I am very new to this server world, you all would have realized that by my first question, so can you guys suggest some books that can be the starting steps to gain knowledge in this area.

  2. I ran the following command

  • mpstat -w 1 2 attached is the result (cmd_2)
  • Now my question is CPU usage of each CPU totals to be 100.1 & ALL showing cpu usage greater than 100. Why is the %ec value greater than 100
  • How can I effectively estimate the net CPU Usage of the server
  • My primary task is to get a fair bit of idea of the CPU usage and to understand if there is scope and capacity to run new jobs.

Regards
Saurabh

start from commands

lparstat -i
prtconf |head

Online virtual cpus are numbers of cores your lpar is able to use
If you machine is set to uncapped it also means maximum of cores you will be able to use if they will be needed and available for your lpar

Entailment or physical CPU is guarantied processor value that will be always available for your lpar

the percentage of Entailment you see in vmstat is a value that show how much cpu you are using compering to guarantied value

Also depending which type of processor you are having Power4,5,6,7
You can have 1 -4 x threats per core
It means that it will multiple Vrtual CPU number with smp value

It looks like you have Power 5 or Power6 server with 2 Cores Entitlement with 4 Cores Virtual and 8 Threats

Well, first of all if you are not so sure about PowerVM virtualization, I would recommend that you take look at the below site:
https://www.ibm.com/developerworks/wikis/display/virtualization/Home

It also includes lots of videos on how PowerVM works, what LPAR is, what physical CPU and virtual CPU, how PowerVM manages CPU and memory pools, and many more.

There are very good IBM RedBooks as well on PowerVM and virtualization.

Besides the specific features, PowerVM hypervisor is no different than VMWare ESX or Citrix XEN. LPAR is just a fancy name of a "virtual machine". But PowerVM leaves the others out of the race taking full advantage of Power systems in optimized usage of the resources. Thus, very interesting to learn.

Good that you have interest on the platform you are working on. I have a very vague idea about SAS, but I am one of the admins who is responsible for the AIX and other UNIX servers on which SAS runs for our client.

It's always a good idea to be aware of the surroundings! :b: