The Intel 12th Generation (Alder Lake) CPU is the first Intel consumer CPU that introduces a new hybrid big.LITTLE CPU architecture. This new hybrid Intel CPU architecture integrates two types of CPU cores: Performance-cores (P-cores) and Efficiency-cores (E-cores) into the same physical CPU die. For more information about this new hybrid Intel CPU design, check out this resource HERE.

These new hybrid Intel CPUs have also become the defacto standard for the Intel NUCs starting with the 12th Generation Intel NUCs (Dragon Canyon, Wall Street Canyon & Serprent Canyon), which were released last year. While the ESXi scheduler does not support or understand this new consumer CPU architecture, it can function with ESXi but does require an ESXi kernel boot option, which I have documented HERE, that tells ESXi to ignore the CPU differences.

While this has been an acceptable workaround, there are no guarantees on how the ESXi scheduler will behave. Furthermore, you will also not benefit from Hyper-threading (HT) on the P-cores as the E-cores do not contain HT-enabled cores and hence HT is also disabled by ESXi. A slightly better workaround is to actually disable the E-cores, which would give you uniform CPU P-cores and also access to HT. During my initial investigation, I was never able to figure out how to disable the E-cores within the Intel NUC BIOs and I had assumed it was just not possible.

I recently had re-inquired about this configuration change and came to learn that it is possible to change both the P-core and E-core settings within the Intel NUC BIOs, it was just not very intuitive!

[Read more...]