Re: Virtual memory - user space kernel space

On Feb 8, 1:45 pm, "SaranJothy" <saranjo...@xxxxxxxxx> wrote:
Hi,
I m having some questions in Linux memory management.
I m considering about 32 bit machine only.
If you have a 512 MB of memory, how it is divided between kernel space
and user space?

you bumble virtual and physical memory. kernel divides _only_ virtual
memory between kernel space and user space,
physical memory are share to both. so, if for example, I want to
allocate n mb from user space, i can get some virtual address p
associated with physical page g.
and if i after it will try to allocate n mb from kernel space i can
get some virtual address i, associated with the same physical page g.
it's normal.


What is the link between this division and 3GB userspace and 1 GB
kernel space division.
Is the 3G/1G division is for virtual memory?

yep

Is the total Virtual memory can be 4G only? I mean is it the maximum?


nope. intel, for example, support PAE feature, that performs 64G
virtual space.

Thanks in advance.

regards
SaranJothy


.

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