Intel Clearwater Forest processors made an appearance in a Linux kernel patch which was shared earlier today. This is significant, as Phoronix notes, because it is the first patch addressing Clearwater Forest, an upcoming all E-Core Xeon processor family that is expected to launch sometime in 2025. Moreover, in the patch notes, we see that Clearwater Forest chips will use Atom Darkmont cores.
As a first patch, the support for Clearwater Forest delivered in this release is extremely limited. This is typically the way things happen, though, and it is still pleasing to see information at such an early stage. Specifically, all the developers have added to this new Linux kernel patch concerning Clearwater Forest is the new 0xDD (221) model number for these CPUs. Additionally, the patch appears to confirm that Clearwater Forest Xeons will use Intel’s Atom Darkmont (18A) cores.
If an all E-Core Xeon sounds familiar, it is because Intel is busy getting Sierra Forest ready for launch. Sierra Forest will be the firm’s first all E-Core (Atom Crestmont) Xeon processor family and is due sometime this summer. Intel's Open-source Linux software engineers have already laid the groundwork for Sierra Forest, enabling hardware support in the OS as well as related open-source projects.
Sierra Forest is an interesting server processor product that appeared on Intel roadmaps last March, and was first officially detailed last August with up to 144 E-Cores, but the product family was extended in September with the announcement of CPUs packing up to 288 E-cores.
We have seen some unofficial benchmarks from what appears to be a system packing a 144 core Sierra Forest CPU. If the Geekbench scores we saw in December were genuine and representative, the upcoming Xeons will pack a big punch in multi-threaded workloads, and they should do so efficiently. Meanwhile, single-core performance was predictably lackluster, but it shouldn’t matter for the intended workloads. It will be interesting to see how Intel steers the performance of Clearwater Forest on 18A to be a worthy second-generation release.
We hope to see some more leaks, spills, and sideways glances at both Sierra Forest and Clearwater Forest Xeons in the coming weeks and months as representatives of a new breed of server chips from Intel’s stables.
