Virtual memory upper limits are set by the OS$,$ for

example on $32-$bit windows the limit is $16$TB and

on $64$ bit windows the limit is $256$TB$.$ Forget the

idea that virtual memory is limited by the size of

pointers on machine. Virtual memory limits are

m$=$not the same as addressing space. You can

address more virtual memory than is available in

your pointer based address space using paging.

Note the sources of this.