Re: [Qemu-devel] [PATCH 0/3]: BLOCK_WATERMARK QMP event

[Avi Kivity <avi@redhat.com>]

On 03/11/2010 04:19 PM, Anthony Liguori wrote:
>
>> But honestly, while I do understand your point, this feels like a hack
>> to work around shortcomings of an interface. So what we need to decide
>> is which criterion outweighs the other in practice.
>
> If I understand the use case correctly, what this really boils down to 
> is that you want to create a growable image on top of a non-growable 
> device.  The management tool then deals with growth using this interface.
>
> I'm somewhat inclined to suggest that the proper way to support this 
> is to teach qemu how to grow the LVM volume like it would grow any 
> normal file.

Interesting.  Could use a helper or helper.so, or a new block format 
driver (block/lvm.c).  Still, if management is actually interested in 
the change, not just to grow the volume (perhaps to handle out-of-space, 
or to check against a global disk low condition), the helper/driver then 
needs to communicate with the management system, which is awkward.

I guess it's workable though.

-- 
error compiling committee.c: too many arguments to function