Joined: 03 Oct 2009 Posts: 1786 Location: Bloomington, IL
How long is a piece of string? You will not get any meaningful help on this by posting on the Internet; your managers need to turn loose of some real money and bring in consultants for hands-on analysis.
Joined: 06 Jun 2008 Posts: 8280 Location: Dubuque, Iowa, USA
"Cost savings" only applies if the site has some form of chargeback system in place. Otherwise, sites like mine that don't do chargeback have the fixed cost of the system, whether the system is 1% utilized or 100% utilized.
You may not be able to reduce the number of online transactions since that number will be a function of the work being performed and the coding of the applications being executed.
Do the standard things -- look for string waits in CICS and add strings if needed, make sure there's plenty of buffers both online and for batch access, investigate BLSR if your batch programs do a lot of random reads.
First step is always to figure out exactly what you want to reduce. Is it CPU usage, is it Tapes allocation, is it i/o counts, is it wall clock time?
Once you have that answer in hand, the rest can fall into place quickly. For example, you decide you want to reduce i/o. This means you can add buffering to your VSAM/QSAM jobs and get big reductions in i/o. The CPU time may go up a bit, but the cost offset of the i/o could possibly be greater.
Something like "high transaction count" is abstract. Are you getting charged by the transaction? If not, then why does anyone care about the count?
I've seen people, smart people, go down all the wrong rabbit holes when it comes to performance. The biggest mistake I see is the lack of before and after testing. Because I actually use my real name, I can't tell you too many details, but I can say that spending six months changing a few IMS calls to be path calls will NOT save you hours of wall clock time. However, spending a week finding out which programs are on the critical path, then using STROBE to see what they are doing, then removing the one IMS call that doesn't really need to be there CAN save you four hours a day.