What are the different LPARs in mainframes?

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Shailndra Pandey
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What are the different LPARs in mainframes?

Post by Shailndra Pandey »

Hi,

What are the different LPARs in mainframes?

I read about the definition of maiframe LPARs like this
Logical partitions (LPARs) are, in practice, equivalent to separate mainframes.

Each LPAR runs its own operating system. This can be any mainframe operating system; there is no need to run z/OS®, for example, in each LPAR. The installation planners may elect to share I/O devices across several LPARs, but this is a local decision.

The system administrator can assign one or more system processors for the exclusive use of an LPAR. Alternately, the administrator can allow all processors to be used on some or all LPARs. Here, the system control functions (often known as microcode or firmware) provide a dispatcher to share the processors among the selected LPARs. The administrator can specify a maximum number of concurrent processors executing in each LPAR. The administrator can also provide weightings for different LPARs; for example, specifying that LPAR1 should receive twice as much processor time as LPAR2.

The operating system in each LPAR is IPLed separately, has its own copy of its operating system, has its own operator console (if needed), and so forth. If the system in one LPAR crashes, there is no effect on the other LPARs.

In a mainframe system with three LPARs, for example, you might have a production z/OS in LPAR1, a test version of z/OS in LPAR2, and Linux® for S/390® in LPAR3. If this total system has 8 GB of memory, we might have assigned 4 GB to LPAR1, 1 GB to LPAR2, 1 GB to LPAR3, and have kept 2 GB in reserve. The operating system consoles for the two z/OS LPARs might be in completely different locations.

For most practical purposes there is no difference between, for example, three separate mainframes running z/OS (and sharing most of their I/O configuration) and three LPARs on the same mainframe doing the same thing. With minor exceptions z/OS, the operators, and applications cannot detect the difference.

The minor differences include the ability of z/OS (if permitted when the LPARs were defined) to obtain performance and utilization information across the complete mainframe system and to dynamically shift resources (processors and channels) among LPARs to improve performance.
But I came to know about differnt LPARs types like CP, ICF, IFL, SAP and IFP. Can you please guide where can I get the detailed information about them. Any help would be great.
enrico-sorichetti
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Re: What are the different LPARs in mainframes?

Post by enrico-sorichetti »

cheers
enrico
When I tell somebody to RTFM or STFW I usually have the page open in another tab/window of my browser,
so that I am sure that the information requested can be reached with a very small effort 8-)
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Robert Sample
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Re: What are the different LPARs in mainframes?

Post by Robert Sample »

But I came to know about differnt LPARs types like CP, ICF, IFL, SAP and IFP.
You missed zAAP and zIIP.
enrico-sorichetti
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Re: What are the different LPARs in mainframes?

Post by enrico-sorichetti »

and ..
what about ZOT :D
cheers
enrico
When I tell somebody to RTFM or STFW I usually have the page open in another tab/window of my browser,
so that I am sure that the information requested can be reached with a very small effort 8-)
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