Advanced Micro Devices Inc (AMD)

[Haddock]

The snowball starts rolling:

http://www.x86-64.org/lists/discuss/msg03806.html

Our work involves chip-design, typically w/ processes that have sizes >2GB
(often in excess of 4GB, but then we have use Sun boxen for it and pay the
price in time and money). In Linux, one can adjust the kernel/user memory
split up to about 3G/1G comfortably on 32-bit processors (and obviously,
the OS in 32-bit mode). We do this to get a bit more headroom for our
(large) jobs.

What I want to verify, is that on a box running a 64-bit kernel
(i.e. compiled arch == x86_64), a 32-bit user-space app will be able to
use all 4GB (or nearly all of it, perhaps AGP/PCI windows etc cut out a
small amount at the top). Our software vendors (closed-source) have not
released their x86_64 ports yet, so we will be stuck with 32-bit apps
until probably this fall. _However_ if we can get that extra 1GB of
memory (per process), it will help quite a bit in the short-term (and
probably spare us buying another Sun).

Of course, the answer is that they can use 4Gbytes of memory on a 32 bit app with 64 bit Linux. This will tide them over until the fall, when the ported app is due.