ubuntu-mips team mailing list archive

[Kai-Cheung Leung <kcleung@xxxxxxxxxxxxxxxxxxxxx>]

>  >
>  >     +-----+----------------------+--------------------+
>  >     |     | Kernel address space | Userland           |
>  >     +-----+----------------------+--------------------+
>  >     | o32 | 32 bit       (< 4GB) | 32 bit     (< 3GB) |
>  >     +-----+----------------------+--------------------+
>  >     | n32 | 64 bit   (unlimited) | 32 bit     (< 3GB) |
>  >     +-----+----------------------+--------------------+
>  >     | n64 | 64 bit   (unlimited) | 64 bit (unlimited) |
>  >     +-----+----------------------+--------------------+
>  >
>  > Figures in parentheses mean amount of usable memory, virtual for
>  > userland, physical for kernel space.  unlimited means in pratice,
>  > mathematically correct: 2^64 B.
>  >
>  > Please correct me if I got anything wrong.
> Yes, the main differences between different ABIs lay on the registers
> usages, length of data type, address space and so on. More details could
> be gotten by Google. And also you could refer to the book "see mips
> run" and some specifications. Thanks.


You said that in n32, the "userland" only has 3GB.  Does the "Userland
refer to the max logiccal address range available to a process, or
*all processes* together?  i.e. if hardware allows, will I be able to
run 100 n32 applications, each takes 2GB of memory?

Also if the kernel supports 64-bit addressing, then would it be
possible to run a mixture of applications compiled with -n32 and -n64
flags simutaneously on an OS that has 64-bit address kernel?

Thanks!

kcleung