I was reading some specs for Ryzen, Threadripper and Epyc(which are all the same basic die). I noticed that someone had listed them as having 48bit physical memory addressing, meaning a maximum shared memory of 256TB. Intel only has 46bit physical addressing, meaning 64TB maximum. SGI has sold 64TB UV systems and cant go bigger, because of Intels memory limitations. I wonder if we will see SGI, Cray or others start making Epyc based large NUMA systems with >64TB of memory, which apparently some customers have been asking for.
