CPU/Core

[rzs0502]

Hi All,

Different people have various opinions regarding this topic.

Eg. When defining an LPAR, you allocate 1 dedicated processor to the partition profile.
Some say that 1 processor indicates the whole processing unit, while others say that you've allocated 1 core from the processing unit.
From my understanding, IBM refer to the core as an individual CPU so the latter applied.
Therefore a 16-way server with quad core processors has 4 processing units each having 4 cores.

Is that the correct view?

Thanks in advance...


"If you always do what you've always done, you will always be where you've always been."

 

[hfaix]

Therefore a 16-way server with quad core processors has 4 processing units each having 4 cores." (16 total cores)

- that's how I view it

 

[DukeSSD]

In short, yes, you have the correct view.

A multi core (power) processing unit is called an MCM: Multi Chip Module, each of the chips in an MCM has 2 cores from power4 onwards and each core is a CPU.

If you had a p690 16 way, or 16 CPU, system (non HPC - don't ask unless you work in a HPC environment) you would have:
2 MCMs
Each MCM will have:
4 chips (power4 so two cores or CPUs per chip)
8 CPUs (power4 so two cores or CPUs per chip)

So 2 X MCM X 4 Chip X2 Core = 16 CPU = 16 Cores.

You could create 16 LPARs, each with one CPU, or 8 LPARs, each with 2 CPUs, etc.

Pre power4 is similar but they only have one CPU or core per chip. Either way you assign, licence software, etc. by the core or CPU, not the MCM.

 

[rzs0502]

Thanks guys.
Finally made sense of Oracle's licensing!

"If you always do what you've always done, you will always be where you've always been."