Re: Overflows (lisp fixnum-bignum conversion)

[kilgallen@eisner.decus.org (Larry Kilgallen)]

In article <dewar.860424609@merv>, dewar@merv.cs.nyu.edu (Robert Dewar) writes:
> Bob Duff said
> 
> <<(By the way, in going from a 32-bit address to a 64-bit address, don't
> think in terms of doubling the size of the address.  In fact, you're
> multiplying the the size of the address space by about 4 billion, which
> is an awful lot.  Much bigger than the switch from 16 to 32.  It's hard
> for me to even imagine how big 2**64 bytes is.)>>
> 
> Yes, but this is address space, not actual data in a program, if you start
> mappiong entire file systems into virtual memory, you can be surprised how
> fast the 64 bits gets eaten up.

I don't see it going that fast.  Disks I use hold 1 GB, while others
can hold 4 or 9 GB.  64 bits allows me to address the contents of about
2,000,000,000 of the 9 GB drives.  How many disk drives have ever been
built ?

Larry Kilgallen