From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: [RFC] limit dom0 memory using Xen's dom0_mem command
	line option
Date: Tue, 16 Aug 2011 11:00:35 +0100
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Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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This set of patches limits the amount of memory dom0 can use by using
Xen's dom0_mem=max:NNN command line option.  This can make extra
memory available because less memory is wasted on page tables that are
never used and fewer pages are reserved for low memory situations.

In addition, the extra pages can be in two regions which allows more
low memory to be available if dom0 intially starts with less than 1
GiB.

Xen requires the patch "x86: use 'dom0_mem' to limit the number of
pages for dom0" to provide the correct information in the
XENMEM_maximum_reservation memory op.

Instead of this approach would it be better to limit dom0 memory to
the initial number pages and use the recently added memory hotplug
support in the balloon driver for all reservation increases?

David