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From: "David S. Miller" <davem@redhat.com>
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Date: Mon, 21 May 2001 04:04:28 -0700 (PDT)
To: Andrea Arcangeli <andrea@suse.de>
Cc: Andrew Morton <andrewm@uow.edu.au>,
        Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
        Richard Henderson <rth@twiddle.net>, linux-kernel@vger.kernel.org
Subject: Re: alpha iommu fixes
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Andrea Arcangeli writes:
 > On Mon, May 21, 2001 at 03:19:54AM -0700, David S. Miller wrote:
 > > max bytes per bttv: max_gbuffers * max_gbufsize
 > > 		    64           * 0x208000      == 133.12MB
 > > 
 > > 133.12MB * 8 PCI slots == ~1.06 GB
 > > 
 > > Which is still only half of the total IOMMU space available per
 > > controller.
 > 
 > and it is the double of the iommu space that I am going to reserve for
 > pci dynamic mappings on the tsunami (right now it is 128Mbyte... and I'll
 > change to 512mbyte)

How many physical PCI slots on a Tsunami system?  (I know the
answer, this question is rhetorical :-)

See?  This is why I think all these examples are silly, and we
need to be realistic about this whole situation.

Later,
David S. Miller
davem@redhat.com