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From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [ANNOUNCE] Native Linux KVM tool v2
Date: Thu, 16 Jun 2011 05:24:29 -0400
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Cc: Anthony Liguori <anthony@codemonkey.ws>,
	Alexander Graf <agraf@suse.de>,
	Prasad Joshi <prasadjoshi124@gmail.com>,
	Avi Kivity <avi@redhat.com>, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Ingo Molnar <mingo@elte.hu>,
	Sasha Levin <levinsasha928@gmail.com>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	Asias He <asias.hejun@gmail.com>,
	Jens Axboe <jaxboe@fusionio.com>
To: Pekka Enberg <penberg@kernel.org>
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On Thu, Jun 16, 2011 at 09:21:03AM +0300, Pekka Enberg wrote:
> And btw, we use sync_file_range() 

Which doesn't help you at all.  sync_file_range is just a hint for VM
writeback, but never commits filesystem metadata nor the physical
disk's write cache.  In short it's a completely dangerous interface, and
that is pretty well documented in the man page.