Is anyone using SimH or QEMU with an old architecture/OS in production?

Question

A few years ago a company I helped a company I used to consult for finally transition a business-critical application off of their physical Solaris 8/SPARC servers... onto emulated Solaris 8/SPARC using qemu. The ancient code (which was originally written in FORTRAN in the 1960s and was originally converted using f2c) was still being maintained on a Solaris 2.6 server using the Sun proprietary compilers, and relied on a core static library they purchased from a third-party which they only had in binary form. Luckily it was all 32-bit because qemu can't boot 64-bit Solaris yet, and it was only about 6-7 years ago that qemu finally got fixed to flawlessly emulate the sun4m architecture (we had started testing it about 12 years ago). While I don't consult for them anymore and no longer can access their systems, I highly doubt they've replaced it today as it was really a critical part of the business. They know they have to at some point, if only because the people familiar with it won't live forever, or because of the 2038 problem, but it does work, and works a lot faster than it used to on the physical servers.My HN question is... who else is using either qemu to emulate an old architecture or OS, or even SimH, for actual _production_ work? I know IBM is very unpleased if people try to run production apps on Hercules, but that's at least still a living architecture and OS. I want to know who is keeping the dead alive to do real work!

mikewarot · Accepted Answer

When I was working at the gear shop, they had some DOS based code that they couldn't update, but gave numbers critical to setting up the gear generators. I put it all in VirtualBox, rerouted the printer to a file in the VM, and they were able to print the number they needed.If you have a system in production, making any changes risks the viability of the enterprise. The general public doesn't really understand the nature of these risks, and tends to blow them off.

notacoward · Answer

I don't know about using it in production, but I worked at a company using simh and relatives to develop a new machine architecture. Quite successfully, I might add. An amazing amount of code written to the emulator ran immediately, without change, on the first real PCBs. Impressive stuff.

oso2k · Answer

This place wouldn&rsquo;t happen to be in Pasadena would it?

euanc · Answer

At Stabilize we support companies to run enterprise software securely and access it via a web browser. We use various emulators on the back-end https://stabilize.app/.