Re: What to expect with the 2.6 VM

Martin J. Bligh
2003-07-01T20:08:09Z

>> In 2.4, Page Table Entries (PTEs) must be allocated from ZONE_ NORMAL as
>> the kernel needs to address them directly for page table traversal. In a
>> system with many tasks or with large mapped memory regions, this can
>> place significant pressure on ZONE_ NORMAL so 2.6 has the option of
>> allocating PTEs from high memory.
>
> You probably ought to mention that this is only needed by 32 bit architectures
> with silly amounts of memory installed.

Actually, it has more to do with the number of processes sharing data,
than the amount of memory in the machine. And that's only because we
insist on making duplicates of identical pagetables all over the place ...

M.