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