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Date: Tue, 22 Jul 2008 15:22:54 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] qcow2 - safe on kill?  safe on power fail?
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To: qemu-devel@nongnu.org

Avi Kivity wrote:
> >Seems like a band-aid to me as SIGKILL is still an issue.  Plus it 
> >would involve modifying all disk formats, not just QCOW2.  I'd rather 
> >see proper journal support added to QCOW2 myself.
> 
> Journalling is so out of fashion.  It's better to sequence the 
> operations so that failure results in a leak instead of corruption.

That would be find.  If there's too much leakage after a time, it
would be easy enough to "qemu convert" to recreate the image without
leakage.

Or trees, trees are the new journals... :-)  Still there's always
the possibility of errors to recover from, no matter how careful.

-- Jamie