AIX - CPU Utilization -Some points

                                        CPU Utilization in AIX . 
                                      =====================

 Here in  our example , we will try to understand actually how are the CPU entitlement parameters working in AIX .

 Let us  try to understand through different scenario's .

 Taking the below example 


 Mode                                           : Uncapped
Entitled Capacity                          : 3.00
Online Virtual CPUs                     : 20
Maximum Virtual CPUs                : 30
Minimum Virtual CPUs                 : 2
Minimum Capacity                        : 1.00
Maximum Capacity                       : 10.00


 Entitled Capacity : This LPAR is entitled/guaranteed  to get 3 CPU .
Minimum Capacity :  minimum requirement to start this LPAR is 1 CPU .
Maximum Capacity : Maximum entitlement for this LPAR is 10 CPU .

Question comes here .,what is actually maximum Capacity and how it works ?
ans) Maximum Capacity parameter comes into picture when we talk about DLPAR operations . It means that we can increase the  Entitled Capacity  online to the Maximim Capacity Value i.e. in this scenario to 10 . 
                                  Maximum entitlement doesn't have any relation with the CPU utilization  of LPAR . Many times noticed people have mis-conception that this is the maximum value till what CPU utilization of the LPAR can go .

Ques) In this scenario ,what can be the maximum CPU utilization this LPAR can achieve ?
ans) This LPAR is un-capped ,it means that it  can go upto maximum limit as per the configuration and requirement  subjected to the fact that CPU pools are having enough free CPU.
     When we talk about it can go to maximum limit  as per the configuration ,here comes into the picture the "online virtual CPU "  .As we know that , virtual CPU use power of 1 CPU as per the requirement .     The maximum  CPU utilization of this LPAR depends on the value of "online virtual CPU's "  and the free CPU's available in CPU Pools.
Here in this scenario , This LPAR  CPU utilization can go  maximum  upto 20 CPU   subjected to the fact that it that enough CPU resources in the CPU Pool .


Taking the same scenario but the "CPU Mode is capped"


Mode                                            : capped
Entitled Capacity                          : 3.00
Online Virtual CPUs                     : 20
Maximum Virtual CPUs                : 30
Minimum Virtual CPUs                 : 2
Minimum Capacity                         : 1.00
Maximum Capacity                        : 10.00



Ques) In this scenario ,what can be the maximum CPU utilization this LPAR can achieve ?
ans) The CPU mode for this LPAR is capped means that in any case it can't go above the entitled Capacity . Here in this case , Entitled Capacity is 3 CPU , means  CPU utilization
 of this LPAR can't go beyond 3 CPU .