> it's reasonable to expect systems will exist with > 256TB of memory in a single machine.
Note that this is a limit for address space, not for physical memory. You can need that address space e.g. for mmaping of large files. And disk arrays with files larger than 256 TB are realistic even today (that is just 16x 16TB HDD).
Note that this is a limit for address space, not for physical memory. You can need that address space e.g. for mmaping of large files. And disk arrays with files larger than 256 TB are realistic even today (that is just 16x 16TB HDD).