From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: JFYI: ext4 bug triggerable by kvm
Date: Mon, 16 Aug 2010 14:42:37 -0400
Message-ID: <20100816184237.GA16579@infradead.org>
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 <4C694E7D.3060600@codemonkey.ws>
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Cc: Michael Tokarev <mjt@tls.msk.ru>, KVM list <kvm@vger.kernel.org>,
	Kevin Wolf <kwolf@redhat.com>
To: Anthony Liguori <anthony@codemonkey.ws>
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On Mon, Aug 16, 2010 at 09:43:09AM -0500, Anthony Liguori wrote:
> >Also, ext4 is _very_ slow on O_SYNC writes (which is
> >used in kvm with default cache).
> 
> Yeah, we probably need to switch to sync_file_range() to avoid the
> journal commit on every write.
> 

No, we don't.  sync_file_range does not actually provide any data
integrity.