After debugging a recent issue with using VMware Workstation and Intel Hybrid CPUs, it gave me an idea about an experiment to try with ESXi and Intel Hybrid CPUs.
As a refresher, starting with the Intel 12th Generation (Alder Lake) CPU, a new hybrid big.LITTLE CPU architecture was introduced for consumer Intel CPUs. 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. The ESXi scheduler does not and has no current plans to support this new Intel Hybrid CPU architecture, especially as this type of architecture is nowhere to be found in traditional Enterprise datacenters and is only limited to Intel Consumer CPUs.
The current recommendation to work around the non-uniformity of the CPU cores is to either disable the E or P-cores within the system BIOS, thus making the system "uniform" and allowing ESXi to run like a normal x86 system. While you can apply a workaround to have ESXi ignore the non-uniformity of the CPU cores, in addition to the non-deterministic behaviors, random PSOD can also occur due to scheduling across two different types of cores.
I was curious to see whether applying ESXi CPU affinity on a VM using Intel Hybrid CPU Cores might yield a different outcome?
