From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: Possible regression: XEN 4.0.0 total_memory decrease
Date: Thu, 15 Apr 2010 19:34:56 +0100
Message-ID: <C7ED1AE0.11757%keir.fraser@eu.citrix.com>
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On 15/04/2010 19:26, "Alex Williams" <awilliams@iweb.com> wrote:

> Yes you're correct! Both hosts have dom0_mem=512M set.
> 
> Xen 3.4.2: free_memory            : 3514
> Xen 4.0.0: free_memory            : 3523
> 
> So now it appears to be a free memory INCREASE caused by this 'bug' ? ;)

The reason for the increase is that for various technical reasons we used to
carve off 16MB of memory into a separate memory allocator used for Xen's own
internal book-keeping structures. We no longer have that and so that 16MB is
now part of the ordinary allocation pool. So you see 9MB extra in that pool,
which is that 16MB minus the book-keeping allocations (about 7MB of them)
which now occur from the unified pool.

 -- Keir

> Thank you!!!