alt Hacker NewsI wonder if we end up with z series running on arm long term.
The value in z series is in the system design and ecosystem, IBM could engineer an architecture migration to custom CPUs based on ARM cores. They would still be mainframe processors, but likely able to be able to reduce investment in silicon and supporting software.
You can run 1960s System/360 binaries unmodified on modern z/OS. The system also uses a lot of "high level assembler" and "system provided assembly macros" making a complete architecture switch extremely painful and complicated.
They called their new architecture "ESAME" for a while for a pretty obvious reason.