Costing in IBM Mainframes

nirmal.poikaikumaran · New User Joined: 29 Nov 2005 Posts: 66 Location: Bangalore

Hi Team,

I am interested to understand how the mainframe costing is done.

If i reduce the CPU usage of an application would i reduce cost?. What would be the average billing rate of the IBM Mainframe.

Thanks
Nirmal

enrico-sorichetti · Posted: Wed Sep 21, 2011 4:29 pm

all depends on the billing agreement with IBM

nirmal.poikaikumaran · New User Joined: 29 Nov 2005 Posts: 66 Location: Bangalore

Hello Enrico,

I am not sure about my company's agreement. But does the CPU usage be a factor? Please guide upon your experience

Thanks
Nirmal

Bill Woodger · Posted: Wed Sep 21, 2011 4:35 pm

Talk to the person who liases with IBM and you should be able to discover how charging is calculated, and therefore what could be addressed to reduce charging. "Unused" but "allocated" DASD is a potential. To know what sort of things to prioritise, you need to know the detail of the charging.

After you have got initial information, might be worth finding the person in Accounts who is responsible for monitoring this. You will then also know how the bosses will see the results of any savings you achieve.

Robert Sample · Posted: Wed Sep 21, 2011 4:45 pm

Is the machine purchased, leased, or rented? Is system usage capped -- and is your site running well under the cap, near the cap, or over the cap? Are you looking at hardware costs, or overall costs including software? These are the types of questions that would have to be answered before your questions even make sense -- if the machine was purchased, for example, you could reduce CPU usage to zero and costs for the hardware would not go down one penny since the money was already spent. Depreciation and residual value have to be considered, as well.

The ONLY time you can talk about "average billing rate" for a mainframe would be if you are running your programs at a third-party vendor site that billed computer usage. IBM contracts can vary drastically, so there probably is no such thing as an "average" billing rate.

Hardware costs are only a part of the picture, too. IBM charges monthly fees for everything from the operating system to compilers to utilities. The montly charges may exeed the monthly maintenance fee for the hardware. And the monthly software charges probably won't go down if one application's CPU usage goes down.

Furthermore, you haven't mentioned anything about third-party software costs (from companies such as CA, Compuware, BMC, ASPG, SEA, and so forth), which can be a substantial portion of the overall costs of the mainframe. These contracts can be usage-based, or time-based, or some combination of the two, so these costs may -- or may not -- go down if one application starts using less CPU.

Bottom line: your questions sound reasonable, but they are very complicated to answer since so much depends upon the individual site and its contracts with vendors. The only way to answer your questions would be to consult your site support group. And it is very possible that they don't know since the contract details may not have been provided to them -- if so, only your management could provide you an answer.

vasanthz · Posted: Wed Sep 21, 2011 4:48 pm

As said earlier, it depends upon the agreement, in some cases there might be a flat charge for the CPU used.
No matter if you use too much or don't use at all, there will be a fixed rate charged.
For DASD media charging may be 'usage based' (allocated) or the number of DASD volumes(unallocated as well on the volume).
Edited: Did not see Robert's reply