From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH v2 7/8] xen/x86: Use 2M superpages for
 text/data/bss mappings
Date: Wed, 24 Feb 2016 13:21:52 +0000
Message-ID: <56CDAE70.6070100@citrix.com>
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To: Jan Beulich <JBeulich@suse.com>
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On 24/02/16 13:17, Jan Beulich wrote:
>>>> On 23.02.16 at 17:31, <andrew.cooper3@citrix.com> wrote:
>> This balloons the size of Xen in memory from 4.4MB to 8MB, because of the
>> required alignment adjustments.
> Interesting - on v1 it was 12Mb iirc, and aiui you folded just one
> pair of 2M pages, which would yield 10M now; did you perhaps
> not account for .text spanning 2 large pages, due to the 1M bias
> it starts at? But anyway...

The original 12 was me just counting 6 superpages.  I forgot to account
for the 1 released back because of .init (which I suppose is now in the
following patch).  That, combined with the alignment drop results in 4
in-use superpages after boot.

~Andrew