Very Computer

Hi all,

I apologize if this is a faq, but I can't seem to find the answer online.
Anyway, what is the maximum amount of memory the current x86 Linux kernel
can address per process?  I am running large digital circuit simulations
and have recently blown out the 2GB per-process limit of WinNT.  Since our
simulation tools are also available on Linux, we were hoping we could get
a little more headroom for our x86 boxes before having to jump to a 64-bit
processor system.  I believe I've heard the figure 3.75GB tossed around,
but I can't find anything definite.

Thanks,
Paul

Paul Secinaro wrote

Quote:

>I apologize if this is a faq, but I can't seem to find the answer online.
>Anyway, what is the maximum amount of memory the current x86 Linux kernel
>can address per process?  I am running large digital circuit simulations
>and have recently blown out the 2GB per-process limit of WinNT.  Since our
>simulation tools are also available on Linux, we were hoping we could get
>a little more headroom for our x86 boxes before having to jump to a 64-bit
>processor system.  I believe I've heard the figure 3.75GB tossed around,
>but I can't find anything definite.

Its 3GB by default in 2.2.16, I don't think there is an option to adjust
it upwards. Unfortunately because of a pretty fundamental architectural
feature (or bug) the total size of physical memory plus the total size
of the virtual address space is limited to 4GB. So with 3.75GB address space
you could only use 256MB of RAM.