From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: madvise() not triggering page discard with MMU-notifiers
Date: Tue, 19 Aug 2008 22:16:55 -0300
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Cc: Avi Kivity <avi@qumranet.com>,
	Andrea Arcangeli <andrea@qumranet.com>,
	kvm-devel <kvm@vger.kernel.org>
To: Anthony Liguori <aliguori@us.ibm.com>
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Hi Anthony,

On Mon, Aug 18, 2008 at 05:04:25PM -0500, Anthony Liguori wrote:
> Attached is an updated migration patch.  It does not appear, however,  
> that madvise() is triggering discarding of pages even with an  
> MMU-notifier enabled kernel.  I take it that this is because we're still  
> holding a reference count to the page when it is in the shadow page  
> table?  Any ETA on when this will change?

Shadow references should be dropped via kvm_unmap_rmapp -> rmap_remove. 

So the symptom is that RSS for the task does not decrease accordingly to
the ballooned down size?