This IDC study presents results of an IDC research project conducted to gain insights into usage patterns for IBM System z mainframes and to better understand user attitudes and user intentions concerning the use of such systems in the future. To gather information, IDC conducted a Web-based survey of mainframe-knowledgeable IT experts and decision makers during the winter and spring of 2009. A total of 300 respondents provided data regarding the usage patterns they see in their sites — and data regarding their future intentions regarding acquisition of System z and software to run on the mainframe platform. Follow-up in-depth interviews were conducted with five selected mainframe users by IDC analysts to add depth to the analysis. Only IBM mainframe users were included in the survey population.

The study identifies the emergence of a blended, or hybrid, approach to computing on the IBM System z platform. "Customers are finding that new workloads, including Linux-based and Java-based workloads, can leverage the mainframe's built-in security and high levels of availability, by running them on mainframe specialty processors, such as the IFL, zIIP, and zAAP processors," said Jean S. Bozman, research vice president, IDC's Enterprise Platforms Group.

Changes in the storage environment are also expected. "As more people access these systems, investments in capacity must be made to accommodate increased usage of existing applications," said Laura DuBois, program director, Storage Software. "Additionally, usage growth will be driven by a range of new workloads coming onto the mainframe platform, and from applications that need access to mainframe-hosted databases."

Many mainframe users reported that they can plan another wave of investments in the System z platform over the next 2–5 years, given the system's high availability, reliability, and security for mission-critical applications. "Customers continue to collect dividends on their System z investments, which makes future investments much more palatable, even in difficult economic times," said Tim Grieser, program vice president, Enterprise System Management Software.