Re: reduce size of pv_pte

[yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi)]

hi,

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> On 04/26/11 00:40, YAMAMOTO Takashi wrote:
>> hi,
>> 
>> the following patch reduces the size of pv_pte, thus pv_entry and vm_page.
>> comments?
>> 
>> YAMAMOTO Takashi
>> 
> 
> Hi, that's interesting. It is cutting a pv_entry from 40 bytes down to
> 32 bytes for 64 bit.
> I've a concern about the runtime requirements because of the
> PHYS_TO_VM_PAGE lookup which might be significant.

if it's significant, it should be improved. :-)

> Do all amd64 machines have only a few physical memory segments?

i don't think so.
linux folks put amazing efforts to speed up their PHYS_TO_VM_PAGE
equivalent for their big irons.

YAMAMOTO Takashi

> 
> Lars