Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

[Ian Campbell <ian.campbell@xxxxxxxxxx>]

On Wed, 2015-08-05 at 12:40 +0100, Andrew Cooper wrote:
> 
> 64K granularity is also similar to 2M/1G superpages in their handling,
> the difference being that 64K can't be subdivided if necessary?

64K is actually a separate basic "granule" (to use the ARM term), i.e.
alternative to the 4K leaf page size, you can still have e.g. 32M super
pages pages if them etc (assuming there are still 512 PTEs per page, I
didn't actually check).

So I think thinking of 64K as a "superpage" while superficially correct
would probably lead to some misunderstanding or confusion at some point.

FWIW there is also a 16K granule available on ARM systems. PPC supports
256K pages too...


Ian

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel