[tyfighter]

This is something I heard through the grape vine years ago, but when you're a very large corporation negotiating CPU purchasing contracts in quantities of millions, you can get customizations that aren't possible outside of gigantic data centers. Things like enabling custom microcode (and development support) for adding new instructions for the benefit of your custom JIT-ed server infrastructure. The corporate entity here is likely a hyperscaler that everyone knows.

[jeffbee]

Some of the public x86 ISA extensions were things that hyperscalers specifically requested.

[clausecker]

Such as?

[dboreham]

Historically the large buyer that could do this was NSA. Men in black would show up and tell you to add a bit population count instruction to your CPU..

[jeffbee]

I think it's doubtful that around the time that POPCNT was added to CPUs the NSA was all that influential. Their big scary data center, which is actually tiny, wasn't built until 2014, while players like Google and Meta had much larger data centers years earlier and were undoubtedly larger buyers of AMD Barcelona / Intel Westmere where POPCNT first emerged.

[Maxious]

eg. "custom Intel Xeon 6 processors, available only on AWS." https://aws.amazon.com/blogs/aws/best-performance-and-fastes...

[renewiltord]

Oracle Cloud used to boast this as something they had. Tuned for OracleDB with more cache, different core count.

And every homelabber has had one of the 7B13 or 9654-variant processors