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Date: Thu, 11 Mar 2010 17:09:56 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 0/3]: BLOCK_WATERMARK QMP event
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Kevin Wolf <kwolf@redhat.com>, uril@redhat.com, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>

On 03/11/2010 05:07 PM, Anthony Liguori wrote:
>>   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.
>
> The management system can poll information from the block driver.  
> Polling is not always evil :-)

In this particular case, it can even poll lvm directly (and I think it 
does), as it needs global information.

So a variant of the raw driver might work here.  Is there any way to 
pass options to nested format drivers?

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