From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <aliguori@us.ibm.com>
Subject: Re: Vitrual TLBs
Date: Mon, 20 Nov 2006 14:00:42 -0600
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To: Liang Yang <multisyncfe991@hotmail.com>
Cc: Tim Deegan <Tim.Deegan@xensource.com>, sameer.ahuja81@gmail.com, xen-devel@lists.xensource.com, Sameer Ahuja <sameer.ahuja@nechclst.in>
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Liang Yang wrote:
> AMD will provide support for nested paging that caches address 
> translations
> to reduce memory accesses in its latest quad-core CPUs. As the hypervisor
> can get pretty bogged down managing all of this and the processor is
> constantly switching from guest OS mode to hypervisor mode and back, 
> Nesting
> page tables and caching memory addresses are ways of freeing things up 
> as it
> cuts down on memory access time.
>
> So Xen may not need such kind of virtual TLB anymore.

If by virtual TLB you are actually referring to shadow paging (and I 
would argue that they are very different concepts), then sorry, I 
misunderstood the initial question.

Yes, Xen supports shadow paging.  Both Intel and AMD are planning on 
supporting hardware shadow paging too in future processors.  I think it 
remains to be see if the hardware shadow paging is flexible enough to 
totally replace software shadow paging.

Regards,

Anthony Liguori

> Liang
>
> ----- Original Message -----
> From: "Anthony Liguori" <aliguori@us.ibm.com>
> To: "Sameer Ahuja" <sameer.ahuja@nechclst.in>
> Cc: "Tim Deegan" <Tim.Deegan@xensource.com>; <sameer.ahuja81@gmail.com>;
> <xen-devel@lists.xensource.com>
> Sent: Monday, November 20, 2006 9:53 AM
> Subject: Re: [Xen-devel] Vitrual TLBs
>
>
>> Sameer Ahuja wrote:
>>> Hi,
>>>
>>> Does XEN have the concept of virtual TLBs?
>>>
>>
>> Not really.
>>
>> Regards,
>>
>> Anthony Liguori
>>
>>> Regards,
>>> Sameer
>>>
>>> _______________________________________________
>>> Xen-devel mailing list
>>> Xen-devel@lists.xensource.com
>>> http://lists.xensource.com/xen-devel
>>>
>>>
>>
>>
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