[GSoC] Defining Memory for MMU page tables at CSB337

Gedare Bloom gedare at rtems.org
Tue Aug 7 14:25:19 UTC 2012


Yes I overlooked that point.. The "Why" factor.

The number of pages that can be used at one time is a concern for
creating either static or dynamic use of MMU. Using big pages allows
to have a finite number of pages and well-defined "zones" of memory.
Big pages also typically map onto the MMU's TLB directly. Small pages
may permit greater flexibility over the memory mapping, but lets a
developer shoot their foot by using more pages than the TLB can
support and thus induce page faults. We must avoid page faults.

On Tue, Aug 7, 2012 at 3:32 AM, Sebastian Huber
<sebastian.huber at embedded-brains.de> wrote:
> I don't think 2nd level MMU support makes sense for a real-time operating
> system.
>
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