6.1 (2009) - Processor Groups to have the KAFFINITY limit be per NUMA node
Xeon E7-8800 (2011) - An x86 system exceeding 64 total cores is possible (10x8 -> requires Processor Groups)
Epyc 9004 (2022) - KAFFINITY has created an artificial limit for x86 where you need to split groups more granular than NUMA
If x86 had actually hit a KAFFINITY wall then the E7-8800 even would have occured years before processor groups because >8 core CPUs are desirable regardless if you can stick 8 in a single box.
The story is really a bit reverse from the claim: NT in the 90s supported architectures which could scale past the KAFFINITY limit. NT in the late 2000s supported scaling x86 but it wouldn't have mattered until the 2010s. Ultimately KAFFINITY wasn't an annoyance until the 2020s.
5.0 (1999) - NUMA scheduling
6.1 (2009) - Processor Groups to have the KAFFINITY limit be per NUMA node
Xeon E7-8800 (2011) - An x86 system exceeding 64 total cores is possible (10x8 -> requires Processor Groups)
Epyc 9004 (2022) - KAFFINITY has created an artificial limit for x86 where you need to split groups more granular than NUMA
If x86 had actually hit a KAFFINITY wall then the E7-8800 even would have occured years before processor groups because >8 core CPUs are desirable regardless if you can stick 8 in a single box.
The story is really a bit reverse from the claim: NT in the 90s supported architectures which could scale past the KAFFINITY limit. NT in the late 2000s supported scaling x86 but it wouldn't have mattered until the 2010s. Ultimately KAFFINITY wasn't an annoyance until the 2020s.