The long-term support (LTS) version of Ubuntu 22.04 is not expected to run on older IBM POWER8 hardware because the developer Canonical is moving its PPC64EL baseline to the newer POWER9 architecture to build software packages. Last week, Matthias Klose mentioned the new plan of Ubuntu 22.04 Jellyfish in a notice, that is, they will use the GCC 11 compiler to increase the baseline requirements of the PPC64EL architecture to POWER9.
In the recent PowerPC edit version update, the development team is already using -march=power8 -mtune-power9 to build. Now, they are pushing further to -march=power9 to further optimize the code generation of the POWER9 processor.
In view of this, Ubuntu 22.04 LTS (and subsequent version updates) is not expected to be used with old POWER8 hardware. The history of POWRT8 can be traced back to 2013 (the hardware arrived a year later), and then POWER9, which was successful in 2017. And the latest one is POWER10 hardware that is working hard to bring it to the market.
Even so, there are still some Linux users who will continue to use POWER8 (because it supports the initial free Raptor Talos system software) instead of upgrading to the POWER9 platform with the Ubuntu 22.04 LTS software update. In fact, this change even confuses some Canonical employees, because their ISO tests (and some other projects) currently rely on IBM POWER8 servers to run (meaning they will also be replaced by POWER9 in the future).
Finally, for the old users of POWER8, if you really don’t think it is necessary, you can still choose the Ubuntu 20.04 LTS Linux distribution that still provides support for the POWER instruction set architecture.