Re: Arm A53
Raspberry Pi is indeed immune to Spectre:
https://www.raspberrypi.org/blog/why-raspberry-pi-isnt-vulnerable-to-spectre-or-meltdown/
So, it seems, is Intel Itanium. See comments at:
https://forums.theregister.co.uk/forum/1/2018/01/25/intel_spectre_disclosed_flaws_november/
Neither Pi nor Itanium is particularly fast, but I posit that most computers in use today are not CPU-bound so it doesn't matter much. Where CPU is crucial, there are often opportunities for parallelism as already mentioned.
In the 1990s, one definition of a supercomputer was, a computer that would change a CPU-bound task to an I/O-bound task. If we expand "I/O" to include reads/writes over the Internet, almost anything I do at home is limited more by slow I/O than by CPU speed. I went through a phase of using a Raspberry Pi as my home computer, and it was not too bad. I gave up in the end, mainly because of low RAM on current versions of the Pi and the absence of MS Office to read attachments.
The main problem using either widely may be that neither ARM as on Pi - nor Itanium - is binary-compatible with x86-64. This isn't an insuperable problem but it implies effort re-compiling and/or developing emulators/translators.
Biting the hand that feeds IT
