There are no announced efforts by either IBM or Microsoft to enable Windows applications to work on the System z. Got it? None, nada, nothing…
Yet, the subject keeps coming up. The most recent to take it up come from a couple of Windows publications, of all place. Both Redmondmag and Redmond Developer published the same piece on the topic, Windows Coming to a Mainframe Near You? by Stephen Snoyer, a New York-based freelance writer.
Similarly, no one except possibly me is offering a plausible business case for Windows on z. It seems that the various Windows on z efforts like Mantissa’s v/OS and WINE are occurring more for the technical or intellectual challenge than for any serious business need.
IBM continually scoffs at the idea of Windows on z. They will give you technical reasons, raise legal issues, and cite business concerns. None appear insurmountable, and even the various IBM spokespeople don’t seem convinced by their arguments.
The best stab at Windows on z has been by Novell, which offers Mono through SUSE Linux running on System z. Mono, as noted here back in early August, is a complete, up-to-date Linux (open source) implementation of an ASP.NET application server that runs on the x86 and System z platforms.
In effect, Mono is a virtual machine for .NET. Using Mono running on SUSE Linux on the System z, organizations can bring their .NET workloads onto the System z. This is not exactly Windows running on the z. While .NET applications usually are Windows applications, not all Windows applications are .NET. So, not every Windows application is a candidate for Mono; only those that are .NET apps and conform closely to the .NET standard. And even then there may be a certain amount of tweaking required.
The real reason so little has happened to move Windows onto the System z is the lack to date of a compelling business case. In addition, data center managers don’t see it as a battle worth fighting. The stars, however, may be aligning for a business case. In short, it is the same as the case for consolidating Linux workloads on the System z.
Enterprises with System z data centers also have tons of Windows and .NET applications pervasive throughout their organizations. Many of these are not even visible to the IT organization. Rather, they are small workgroup and departmental applications running on a stray server with attached storage, maybe even an old PC that has been demoted to serving a single Windows application for a handful of users.
If, and this is a very big if, the organization can smoke out these applications and consolidate them on the z, there appears to be the potential for significant improvements in management efficiency through consolidation and increased application reliability and security through the System z. This, essentially, is the same pitch for Linux on System z.
In this case, the technical issues probably pale in comparison to the political obstacles involved. Users won’t give up control of their Windows applications easily. However, if the savings are real, there should be budget to bribe them to go along.