Re: [Xen-ia64-devel] [PATCH] Use saner dom0 memory and vcpu defaults, don't panic on over-allocation

[Akio Takebe <takebe_akio@xxxxxxxxxxxxxx>]

Hi,

>On Tue, Jul 31, 2007 at 10:43:44PM -0600, Alex Williamson wrote:
>> > +       /* maximum available memory for dom0 */
>> > +       max_dom0_pages = avail_domheap_pages() -
>> > +                        min(avail_domheap_pages() /
>> > +                        16UL, 512UL << (20 - PAGE_SHIFT)) ;
>> 
>>    I assume this heuristic came from Akio's patch in the thread you
>> referenced; can anyone explain how this was derived and why it's
>> necessary?  It looks like a fairly random fudge factor.  Thanks,
>
>I guess it comes from compute_dom0_nr_pages() under arch/x86.
>However I don't know why compute_dom0_nr_pages() is so.
>Anyway It should be different for ia64. While I'm guessing the most
>dominant factor is the p2m table, domain0 building process should
>be revised for the correct estimation.
Yes, Isaku's guess is right.
I use the same logic as x86.

>BTW alloc_dom0_size() may be confusing because it doesn't allocate anymore.
>How about calc_dom0_size()? 
>This isn't essential. very minor issue. Just for my preference.
I agree.

Best Regards,

Akio Takebe


_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel