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Re: [Xen-devel] memory size inside domU less than memory in domU config

To: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Subject: Re: [Xen-devel] memory size inside domU less than memory in domU config
From: Vasiliy G Tolstov <v.tolstov@xxxxxxxxx>
Date: Mon, 20 Jun 2011 18:55:04 +0400
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Jan Beulich <JBeulich@xxxxxxxxxx>
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On Mon, 2011-06-20 at 10:36 -0400, Konrad Rzeszutek Wilk wrote:

> So I tried the same experiment - a physical machine with 'mem=1G' provided
> and an PV guest with 'mem=1G'. The same exact kernel in both cases and got:
> Machine with 'mem=1G' on the command line.
> [    0.000000] Memory: 1022756k/1048576k available (5851k kernel code, 452k 
> absent, 25368k reserved, 2881k data, 688k init)
> PV guest:
> [    0.000000] Memory: 1018888k/1048576k available (5851k kernel code, 448k 
> absent, 29240k reserved, 2881k data, 688k init)
> So a DomU guest "eats" an extra 4MB compared to running it under baremetal.
> (Note, the DomU guest has no balloon space in this example).
> The memblock=debug does provide the info of what the "other" reserved regions 
> are
> and it looks to be the matter of just going through the numbers to figure out 
> what
> it is.

Can You provide pv kernel cmdline and config file ?

Vasiliy G Tolstov <v.tolstov@xxxxxxxxx>

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