Systems for Running Migrated Mainframe Applications
Sizing Examples
Customers have migrated mainframe workloads onto Windows servers ranging from 2 CPUs up to 32 CPUs and more in a single server. Furthermore, customers have migrated mainframe workloads onto single Windows servers, clustered servers, and multitiered architectures, depending upon the size and design of the applications and the architecture chosen by the customer. There is no single mapping of MIPS to MHz or engines to CPUs, but there are plenty of examples to guide you, as well as some emerging benchmark studies. Some sizing examples taken from the case studies published on this site, including assessments of the improvement in performance gained from making the switch, include:
| Customer | Mainframe | Windows Server hardware |
Stanislaus County, CA | ES9000 with OS/390 CICS and COBOL | 4 x 1-CPU servers |
Bertelsmann | 120 MIPS Mainframe | 4 x 2-CPU servers |
Ceridian | 20 small mainframes | 10 x 2-CPU servers in 3 tiers, 2 x 4-CPU for DB |
San Diego schools | Amdahl 5890; 500 CICS progs, 2,300 batch progs | 2 x 4-CPU batch, 2 x 2-CPU online, 2 x 4-CPU DB |
Typical COBOL CICS Transaction Benchmark
Micro Focus published a paper indicating that an 8 CPU Unisys ES7000 could be compared to a mainframe running 1,347 MIPS. While this study is very limited in scope, and the findings may not be generalized for all applications, it is indicative of the size and power of today's Windows servers. A subsequent collaboration between EDS, Micro Focus, and Unisys increased this number to 1,715 MIPS. Download the complete study by clicking here.
SPEC96 Benchmark
IBM submitted two separate test results for the SpecWeb96 benchmark to the SPEC council. Both tests were for 9672 R5 generation mainframes running OS390. Here is a graph of the results:
With these test results, one can compare the capacity of these specific mainframes with other platforms, including Intel servers running Windows. The tests show that, in this particular workload, a Windows-based system using only 2 processors operates at a performance level traditionally handled by approximately 6 processors of an OS/390 class mainframe. Go to the Standard Performance Evaluation Corporation (SPEC) site for information on the benchmark, or go to the specific data for the graph.
Computer Server System Hardware
Windows Server 2003, is available in versions that support from 1 to 64 processors. Above 8 processors, Datacenter Edition provides support for:
| • | 64-way symmetric multiprocessing. For support beyond 32-bit processors, see Windows Server 2003, Datacenter Edition with SP1 for 64-bit Itanium-based Systems. |
| • | Eight-node clustering. |
| • | 1 terabyte (TB) of RAM. For memory support beyond 64 GB, see Overview of Windows Server 2003, Datacenter Edition with SP1 for 64-bit Itanium-based Systems or see Windows Server 2003, Datacenter x64 Edition. |
| • | Non-Uniform Memory Architecture (NUMA). |
Hardware configurations for 32-bit and 64-bit Datacenter Edition are available from Bull, Fujitsu Siemens, HP, IBM, NEC, and Unisys. In addition, check the following links to partners who have systems which that can be been used in mainframe migrations:
Fujitsu Computer Systems
Fujitsu now offers a server with 99.999% uptime that comes bundled with Windows Server 2003 and SQL Server 2000, as well as the Microsoft .NET Framework, but at a fraction of the cost of an zSeries.
Unisys
A real-world availability study of our customers' in-production ES7000 servers shows that 78% of these systems delivered 100% non-stop availability. Overall, the combination of Unisys ES7000 servers and Windows Datacenter operating systems achieved an average 99.996% availability.