Re: [Qemu-devel] [RFC] qed: Add QEMU Enhanced Disk format

[Avi Kivity]

 On 09/10/2010 04:16 PM, Anthony Liguori wrote:
> > btw, despite being not properly designed, qcow2 is able to support 
> > TRIM.  qed isn't able to, except by leaking clusters on shutdown.  
> > TRIM support is required unless you're okay with the image growing 
> > until it is no longer sparse (the lack of TRIM support in guests make 
> > sparse image formats somewhat of a joke, but nobody seems to notice).
>
>
> It's actually pretty easy in QED and it should perform very well.
>
> http://wiki.qemu.org/Features/QED/Trim

If you don't add a free list, this is a pretty bad implementation.  If 
you do, you're back to qcow2's problems.

--
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