Virtual addresses for Pentium Class (386 - 686) machines is 64 Terabytes. 16 bit segments plus 32 bit offsets)
-386wt (Old Intel Guy)
OK. I was using 2 to the 32nd power. Those 16 bit segments get me everytime!
Of course 2 to the 64th is still a lot more...
I don't think segment descriptors get used much in most operating systems. Actually, if segment pointers were 32 bits instead of 64 bits, a 32+32 segmented architecture (or perhaps 24+40) would in a lot of ways be better than a 64-bit linear architecture (use one segment for each memory-managed object and the processor will perform hardware bounds checking). Do any modern operating systems do any such thing?