> Intel cores can run in one of three modes: license 0 (L0) is the fastest (and is associated with the turbo frequencies “written on the box”), license 1 (L1) is slower and license 2 (L2) is the slowest.
Wow, let's give the word "license" semantics not related to software licensing, and cause confusion between L1 meaning "L1 cache" and "license 1".
AIUI this is because the power scheduler gives the core the license to actually execute those instructions. Until it is granted the core must emulate them as multiple vector instructions of smaller stride size.
The terminology isn't great, but I think it's at least better than the marketing terms for the levels which use something like "non-AVX turbo", "AVX2 turbo" and "AVX-512 turbo" for L0,1,2 respectively. This is really confusing because most AVX code will actually run in the faster non-AVX turbo and similarly for AVX-512 as described. So the marketing names are actually too pessimistic.
Wow, let's give the word "license" semantics not related to software licensing, and cause confusion between L1 meaning "L1 cache" and "license 1".