On Thu, 18 Mar 2021 08:47:58 +1100, Attila Fogarasi wrote:
>It is documented in Pops under the SCKPF instruction (which is where I
>would expect). For z/OS it is unique sysplex-wide (i.e. in the scope where
>zos can co-ordinate setting the prefix value). Sole purpose is to resolve
>timestamp collisions.
>
Yes, and further:
Programming Note: The values in the TOD programmable registers of a
configuration should be the same and should be unique within a
multiple-configuration system.
But the question remains, how does the OS determine the values used?
A possible answer is that it's release-dependent, subject to change,
and as long as the constraint above is met IBM chooses not to
document it in order to retain flexibility for future releases.
Wisely, bits 32-47 "must be zero". This effectively reserves them for
use in future models (for flags?)
>On Thu, Mar 18, 2021 at 2:19 AM Farley, Peter wrote:
>
>> I have recently seen a comment in a prior co-worker's assembler code which
>> used STCKE to retrieve the TOD "Programmable Field" contents:
>>
>> "The Field contains a value, assigned by z/OS, which uniquely identifies a
>> current LPAR in the SYSPLEX of machines."
>>
>> Is this a true statement, and if so is it documented anywhere?
>>
>> If true, is the value unique to the CPU or to the LPAR or to the CPC or .
>> . . ?
-- gil
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN
