Intel "Family 6" CPU Era Coming To An End Soon: Code Suggests Cooper Forest & Adams Lake

Since the mid-90's with the P6 micro-architecture for the Pentium Pro as the sixth-generation x86 microarchitecture, Intel has relied on the "Family 6" CPU ID. From there Intel has just revved the Model number within Family 6 for each new microarchitecture/core. For example, Meteor Lake is Family 6 Model 170 and Emerald Rapids is Family 6 Model 207. This CPU ID identification is used within the Linux kernel and other operating systems for identifying CPU generations for correct handling, etc. But Intel Linux engineers today disclosed that Family 6 is coming to an end "soon-ish".

Due to Intel relying on "Family 6" for decades, there's Linux kernel code catering to the Family 6 handling and just expecting model ID comparisons for checking the Intel CPU generation/core. AMD on the other hand has adjusted their Family ID regularly such as Zen / Zen 2 being Family 23, Zen 3 / Zen 4 being Family 25, and now Zen 5 being Family 26. But due to Intel drawing Family 6 to an end, they now need to rework a lot of their CPU ID checking to be future-proof while continuing to handle existing Intel processors.

A set of 74 patches have been readied for adjusting the Intel CPU ID family identification and Intel's future plans of using non-zero values for the extended family field in CPUID(1).EAX. The Linux kernel patch message notes that the transition of Intel ending Family 6 use will come "soon-ish."

Beyond the comments of this happening "soon-ish", in cleaning up the Intel CPU ID Linux code, there are some examples that cite new CPUs in other families may be Douglas Cove / Adams Lake and Intel Sheldonmont / Cooper Forest.

The Douglas Cove and Sheldonmont core names are new disclosures unless random placeholders as are Adams Lake and Cooper Forest though they jive with Intel naming conventions. After Arrow Lake and Lunar Lake is Panther Lake, so the possibility of Adams Lake would be at least 2026 if that's indeed a real codename and would be succeeding Panther Lake. Meanwhile after the Xeon E Sierra Forest is Clearwater Forest, so Cooper Forest could potentially be the successor to Clearwater Forest. Meanwhile, based on earlier Intel Linux kernel patches, it's already known Clearwater Forest will be Family 6 Model 221 and Lunar Lake will be Family 6 Model 189. So at least through those generations Family 6 is keeping up.

This patch series begins the trek of readjusting the Linux kernel code to prepare for future Intel CPUs past the "Family 6" designation. This is an ongoing effort and will likely be ironed out over the coming months for upstreaming into the Linux kernel ahead of these future processors moving beyond the Family 6 era.

Given the timing of things and Intel working on a number of fundamental improvements right now, I have to wonder if this post Family 6 world will be timed for the generation embracing the likes of Intel X86S, Intel FRED, and other significant changes that have been baking. If so, 2026~2027 should be very exciting.