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ItmSysp: affect vs effect...physb vs physc

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ItmSysp: affect vs effect...physb vs physc


Sometimes I am confused whether to use the word "affect" or "effect."  I usually get it right, but I do have to think about it first.  Of course, affect is the verb and effect is the noun.  The confusion can come in because there are rare instances when affect can be used as noun and effect as a verb.  Use your favorite search engine to look up "affect vs effect" and read all about it.
Within the System p world, there can also be confusion over the metrics physb and physc.  Basically, here are the definitions from  lparstat documentation.
physc : Indicates the number of physical processors consumed.

physb: Indicates that the physical processor is busy.

So, the physc metric is physical consumed, which indicates the amount of CPUs consumed or used by the LPAR , regardless of if it is busy or idle.

The physb metric is physical busy, which is the same as physc but without the idle cycles.

With shared partitions, these values will almost be the same, because the partition operating system will give idle cylces back to the hypervisor, minimizing how many idle cycles there are.

In the IBM Tivoli Monitoring for System p AIX Premium agent and UNIX OS agent, these metrics can be found in the following attributes:

physb - Physical_CPU_Units_Used in the Logical_Partition attribute group

physc - Physical_Consumption in CPU_Summary attribute group

To learn more about the System p agents, see the System p agent troubleshooting wiki.

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