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In their testing, even with odd numbers of physical cores, SMT caused an even number of logical cores. Some phones didn't have SMT, and also had an odd number of physical cores, but this was genuinely rare.

Also, they still might not (but probably learned). In this article they imply that each type of CPU core (what they call a "tier" in the article) will still be a power of two, and one just happened to be 2^0. I'm not sure they were around when the AMD Athlon II X3 was hot.

>>> Today I learned this was possible. This was a total "today I learned" moment. I didn't actually think that hardware vendors shipped processors with an odd number of cores, however if you look at the core geometry of the Pixel 8 Pro, it has three tiers of processor cores. I guess every assumption that developers have about CPU design is probably wrong.



The Wii U and Xbox 360 were also triple core machines... both triple core powerpc processors with ATI graphics... Was IBM having a sale on 3 core ppc hardware that year?

I never thought about it before but I actually had to look up die shots to make sure they were not the same processor. and if I can trust the internet they are not. Hell I had to confirm that yes the playstation 3(also ppc, queue x-files theme) only had the one core and it's screwball subprocessers like I remembered.


The world was way richer back then and could afford to spend time and money building desktop scale CPUs for game consoles that sells just tens of millions over few years. They just constantly made new CPUs.

To me, the executive level idea was to spare a core for system and minor peripheral tasks - almost all game console before that generation had single CPU architectures with no resident operating system. Transitioning away from a manually coordinated, single threaded code, to an asynchronous multithreaded programming model, was a challenge in itself, and having to deal with it while operating system forced by the console manufacturer taking away control might have been too much for developers.

(Sega Saturn had 2x SH-2, Dreamcast was to have WinCE on ROM but cancelled. Sega being Sega)


Interestingly, the single PPE core in the PS3 and the 3 cores in the Xbox 360, are pretty much the same core.


I think the SIMD is different between them. I don't remember the details but it was beefed up on the Xbox 360 because it didn't have the SPEs like the PS3.


> each type of CPU core (what they call a "tier" in the article) will still be a power of two

Yeah that's obviously not true, and believing it shows a marked lack of experience in the field. Of the current Xeon workstation lineup, only 3 of 14 SKUs have power-of-2 core counts. And there are consumer lines of CPUs with 6 cores and that sort of thing.


I believe that the assumption was multiple of two, not power of two.


Yeah I both terribly mistyped and misrepresented Anubis' assumption. I'm sorry for that error.


The current Apple TV has 5 cores. No web browser though.


11th gen iPad uses a 5-cores A16. The 14” M3Pro MBP exists in 11 cores (MRX33 / MRX63). There’s also a 9 cores M4, used on the iPad Pro.


And A8x in the iPad Air 2 was tri-core.


When AMD shipped their X3 CPUs I'm pretty sure they didn't support Hyper Threading either.




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