A confusion about LPAR in mainframes.

[Supriya Tank]

Hi,

I have a confusion about LPARs - do they work sequentially or parallel?

I understand that LPAR is a unique device in itself, that means that it's memory, output devices etc. are physically separate.; but its logically two or more systems with their own OS? Can someone please guide me.

[Robert Sample]

If you have a machine with two LPARS defined, both LPARS can be active and getting used simultaneously. There are situations when serialization occurs, but in general each active LPAR on a system can be accessed simultaneously.

[Supriya Tank]

There are situations when serialization occurs, but in general each active LPAR on a system can be accessed simultaneously.

You mean to say that they can work in parallel?

[Anuj Dhawan]

I think, yes - that's the inference.

[Robert Sample]

If the processor has more than one CPU, each CPU can be assigned to one (or more) LPARs. When this occurs, then in a sense the LPARs are running in parallel when they are active. If there is only one CPU, then the LPARs can all be active but only one of them will be using the processor at any given time. However, each LPAR appears to be running by itself.

[Supriya Tank]

Thanks!