Removing a core's SMT aka "hyperthreading" has some modest hardware savings but but biggest cost is that it makes testing and validation much more complicated. Given the existence of Intel's p-cores I'm not surprised they're getting rid of it.
From Intel's perspective, I doubt that's true, when taking into consideration the constant stream of side channel vulnerabilities they were needing to deal with.
You can always do like Sun and IBM and dilute the side channel in too many other threads to make it reliable. IIRC, both POWER10 and SPARC do 8 threads per core.
Lion Cove doesn't remove hyper-threading in general. Some variants will have it so Intel still has to validate it (eventually).
But the first part shipping, Lunar Lake, removes hyper-threading. It may have saved them validation time for this particular part but they'll still have to do it.
Intel has said that they have designed two different versions of the Lion Cove core.
One with SMT, for server CPUs, and one in which all circuits related to SMT are completely removed, for smaller area and power consumption, to be used in hybrid CPUs for laptops and desktops, together with Skymont cores.
I think you’re saying that testing smt makes it expensive, which sounds mostly right to me, though I can imagine some arguments that it isn’t much worse. When I first read your comment, I thought it said the opposite – that removing smt requires expensive testing and validation work.
