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Re: [Xen-devel] query on physical memory map for Xen?

To: pradeep singh rautela <rautelap@xxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] query on physical memory map for Xen?
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Fri, 11 Apr 2008 07:54:13 +0100
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On 11/4/08 07:14, "pradeep singh rautela" <rautelap@xxxxxxxxx> wrote:

> Based on my understanding of the Xen code, I have a small query for you all.
> Xen hypervisor can access only a max of 16GB of physical memory
> directly on x86 architecture.
> Is this correct inference?
> So does Xen hypervisor cannot touch memory about 16G directly? Does it
> employ some kind of temporary mapping like linux kernel to access
> memory above 16G then?

32-bit Xen does not use memory above 16GB at all. 64-bit Xen can use any
amount of memory, and is able to keep a permanent mapping of all of it.

 -- Keir

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