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From: David Mosberger <davidm@napali.hpl.hp.com>
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Date: Mon, 28 Apr 2003 10:53:53 -0700
To: Andi Kleen <ak@suse.de>
Cc: Carl-Daniel Hailfinger <c-d.hailfinger.kernel.2003@gmx.net>,
       Dave Hansen <haveblue@us.ibm.com>, Henti Smith <bain@tcsn.co.za>,
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       Riley Williams <Riley@Williams.Name>
Subject: Re: [Lse-tech] Re: maximum possible memory limit ..
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>>>>> On Mon, 28 Apr 2003 19:13:53 +0200, Andi Kleen <ak@suse.de> said:

  >> Cool. Sorry to be pestering about the 64-bit limits, but can we
  >> really use 2^64 bytes of memory on ia64/ppc64/x86-64 etc.?
  >> (AFAIK, 64-bit arches don't suffer from a small ZONE_LOWMEM.)

  Andi> No. The hardware have far smaller physical limits.

  Andi> Current AMD64 CPUs are limited to 40bit physical, 48bit virtal
  Andi> (the virtual limit per process in the current Linux kernel is
  Andi> 39bits)

  Andi> Itanium 2 afaik support a bit more 50bits (51 or 52, I forgot)
  Andi> physical, probably more virtual.

Itanium 2 supports all 64 virtual address bits and 50 physical bits
(in what way is "1024 times more" "a bit more"? ;-).

	--david