Some 18 months after IBM introduced a new licensing model aimed at reducing mainframe software costs, some users and analysts say moving to it may be more of a challenge and less beneficial in the short term than might have previously been anticipated.
That's because companies that hope to lower mainframe costs by moving to IBM's Workload Licence Charges need to do extensive software capacity planning and asset management beforehand if they want to see any benefits, they said.
"Making the decision to move to WLC is not a trivial task but one that requires an understanding of workload and software configuration," said Chicago-based Lillian Cooper, president of Share, a large-systems user group. "Companies will have to evaluate whether the software savings opportunity, in the face of rising software costs, is worth the extra effort," she added.
IBM didn't respond to repeated requests for comment.
According to Cooper, IBM's decision to delay a licence management and compliance technology called IBM Licence Manager -- which was supposed to have become available last year -- was due to user requests for changes in that technology. But the interim manual reporting implementation makes WLC harder to manage, Cooper said.
IBM introduced its variable WLC in October 2000 along with its 64-bit zSeries mainframes. WLC basically allows users to pay for mainframe software based on the expected average size of their workloads and not on the overall capacity of their systems.
Doing proper software capacity planning is crucial to taking advantage of WLC, said David Ochroch, an analyst at Reiner Associates, a San Francisco-based contract management consulting firm.
Under WLC, users can define the system capacity they need for a particular workload and pay software fees only for that defined capacity. The approach is far more equitable than previous capacity models, in which users paid for software based on the overall size of the system. The larger the box, the higher the software cost, irrespective of actual use, Ochroch said.
However, if the average workload -- measured over a four-hour period under WLC -- exceeds the licensed capacity, the result can be performance degradations and additional software bills, warned Pat Ciacala, president of Ciacala & Associates, a contract management consultancy.
Also, not all users are likely to benefit from WLC as it currently exists, said Al Sherkow, president of I/S Management Strategies. For instance, there are many cases where the sum of the defined capacities licensed by a company could exceed the capacity of a system.
Similarly, a usage-based licensing option available on several crucial pieces of IBM software, such as DB2, IMS, CICS and MQSeries, isn't available under WLC, analysts said.
To take advantage of the financial incentives offered by WLC, users need to understand which software is active in each system image and the capacities required to run the software on these images, Cooper said. Users must use that information to plan image capacities and software deployment on those images and then implement the plan, she explained.