alt Hacker NewsThis feels like a baby step towards Arm being able to emulate z/Arch workloads, maybe with a bit of secret sauce for certain specific operations, which doesn't seem very much like IBM.
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bitwize • today at 3:21 AM
Not even the weirdest thing IBM did to get compatibility between their mainframes and other CPU architectures. To build the XT/370 and AT/370 expansion cards, they custom-ordered modified 68000s that decoded System/370 instructions instead of the 68k instruction set, with most of the instructions handled by the new microcode and the few stragglers software-emulated:
https://en.wikipedia.org/w/index.php?title=PC-based_IBM_main...
stinkbeetle • today at 12:45 AM
ARM can emulate z workloads. https://hercules-390.github.io/html/index.html
(or QEMU, for partition level emulation).
I thought about that, too. I think they’re doing this for the same reason IBM has supported Linux LPARs: since a lot of customers who lease System/z currently probably get overprovisioned hardware that they’ll never fully use, why not try a last-ditch attempt to sell the excess capacity as ARM LPARs?
Now you’re thinking like a Big Blue sales rep.