[undersuit]

>Intel's L3 cache is truly unified. Intel's 28-core Skylake means that the L3 of a Database is TRULY 38.5MB. When any core requests data, it goes into the giant distributed L3 cache that all cores can access efficiently.

This is less true now. Intel's L3 cache is still all on one piece of monolithic silicon, unlike the 4 separate caches of the 4 separate dies on a 32-core TR. But the L3 slice for each core is now physically placed right next to the core and other slices are accessed through the ringbus or in Skylake and later, the mesh. Still faster than leaving the die and using AMD's Infinity Fabric, and a lot less complicated than wiring up all the cores for direct L3 access.

https://www.anandtech.com/show/3922/intels-sandy-bridge-arch...