Problem solve Get help with specific problems with your technologies, process and projects.

Having enough STRINGs around to satisfy concurrent access to files

We are in the process of adding index allocations to all of our CICS regions LSR POOLs. This is in preparation for a Z/Os 1.4 upgrade.

I have been attempting to tune these LSRPOOLS and was told to watch SHARED STRING WAITS TOTAL. On our B&B MAINVIEW monitor this should be as close to 99% as possible. What I have found is that sometimes increasing the LSRPOOL amount will actually reduce the percentage. I know that too big can be bad also. Is there a rule of thumb when adjusting LSRPOOLs?

The general guidance for the quantity and size of LSR buffers is merely to have enough of them. You seem to be after something slightly different and that is to have enough STRINGs around so that you can satisfy concurrent access to the files. If you don't have enough then you can run into performance problems due to unnecessary waits for that resource. I think you need to up the number of strings as 99% seems to be getting dangerously near the concurrent limit.

How you setup LSR is, to my mind, very dependant upon your environment and activity so it's difficult to give general recommendations. However, I suggest you go to the Guide/Share Web sites and see what customer presentations reside therein.

Robert Harris
CICS Technical Strategist -- CICS expert at Search390.com

Editor's note: Do you agree with this expert's response? If you have more to share, post it in one of our .VO7aaqqaAFk.0@/search390>discussion forums.

Dig Deeper on IBM system z and mainframe systems

Have a question for an expert?

Please add a title for your question

Get answers from a TechTarget expert on whatever's puzzling you.

You will be able to add details on the next page.

Start the conversation

Send me notifications when other members comment.

Please create a username to comment.