[mythtv-users] Upgrading from 32-bit to 64-bit and maybe a distro switch?

Preston Crow pc-mythtv08a at crowcastle.net
Wed Jun 17 17:35:14 UTC 2009

On Wed, 2009-06-17 at 13:27 -0400, Johnny wrote:
> Just FYI, 4 GB of RAM *is* a limitation of a 32bit OS. With a 32 word
> size you can only address 2^32 = 4 billion memory addresses. That is
> further limited by some of the address space being reserved for
> hardware addressing, etc. So you can put 8 GB in a 32 bit machine but
> you won't be able to use it.

Sure it can.  It can't use it all at once, but you have to change the
page tables on a context switch anyway, so each process can use almost
4G (minus whatever is reserved for the OS and hardware registers).

The OS just has to be smart enough in setting up the page tables to make
it all work.

More information about the mythtv-users mailing list