Hi Permenides.... On Wed, Aug 8, 2012 at 9:22 PM, Parmenides <mobile.parmenides@gmail.com> wrote:

Hi Mulyadi,

Thanks for your reply. In principle, the physical memory management model can be used for both UMA and NUMA, because we can view UMA as a special case of NUMA.

agree... :)

But, in kernel code, there is some points like

#ifdef CONFIG_NUMA .......

So, I wonder there must be some differences between UMA and NUMA.

maybe this page can explain much much better than me: http://mytechkorner.blogspot.com/2010/12/sparsemem.html not sure, but it seems that sparsemem indeed targetting to handle NUMA. And also memory hotplug...maybe that is the "hole" you refer to. -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com