Parallel Sysplex - subprogram execution

chandraBE · New User Joined: 02 Feb 2010 Posts: 44 Location: Bangalore

Hi

I have a general question on program execution on Parallel Sysplex CICS environment.

When a transaction/Program executes the subprogram, is there any chances the subprogram (issued via LINK) executes on a different CICS region than the transaction/Program which initiated it (when multiple regions are part of SYSPLEX)?

Garry Carroll · Posted: Mon Jun 21, 2021 8:56 pm

A program definition can be used to tell a CICS region where the program is to execute and such a definition is required to execute in a different region to the region where the LINK is issued. If you are using autoinstall and have no program definition, it will execute in the region where the autoinstall occurs - i.e the region where the LINK is issued.

Garry.

Rohit Umarjikar · Posted: Tue Jun 22, 2021 12:34 am

chandraBE · New User Joined: 02 Feb 2010 Posts: 44 Location: Bangalore

Hi Rohit and Garry,

Thanks for your response.

@Rohit, We have some programs which using pointers to pass the parameters and IO data area to subprograms. I was looking at possibility of a subprogram executing in a different region (then those memory address would be different) then it may be an issue.

If these program definition stops it routing to different region then we may be good.

Rohit Umarjikar · Posted: Tue Jun 22, 2021 5:20 pm

As said by Garry , instead of predicting this talk to CICS admin and check the region where it’s defined first as you many no need to do anything here if it’s the same region. But if not you have one of those inter transaction affinity which impacts the DPL and as an extend DTR to resolve. ENQ helps to resolve at great extent the affinities and I don’t remember what changes we did for this type of affinity. You need to test this use case but I am surprised why is this an issue suddenly? Is this a new program or transaction? Or you did not consider this affinity before implementing CICSPlex ? Or are you just doubting the working code ?

chandraBE · New User Joined: 02 Feb 2010 Posts: 44 Location: Bangalore

Hi Rohit,

This an existing program and we just preparing to move to a SYSPLEX environment. Part of this, I am just suspecting if this going to cause an issue if programs using pointers.

From program definition I see Dynamstatus(Notdynamic). And I think this will not dynamically routed to different region. I will check with CICS admin to get more info.

enrico-sorichetti · Posted: Tue Jun 22, 2021 7:40 pm

what happened when You googled with
cics sysplex where will a linked program run

if You had done it You would have bee routed here
www.ibm.com/docs/en/cics-ts/5.5?topic=fundamentals-cics-intercommunication
second link returned ( Your milreage might vary )

where You would have found all You might have wanted to know
about distributed cics processing and cics intercommunication

read the section about DPL and where a linked program would run

Rohit Umarjikar · Posted: Tue Jun 22, 2021 8:49 pm

Also, Are you sure SYSPLEX or CICSPlex? or combination of both. I would advise a caution using these tems but you got the plan of action on this as to where to look , what to look and talk to CICS Admin about the affinities but make sure to test it as well to be sure. Good Luck!
CICSplex, CICSPlex SM, and Parallel Sysplex