Re: [Qemu-devel] Re: KVM call agenda for Apr 27

[Anthony Liguori <anthony@codemonkey.ws>]

On 04/27/2010 08:18 AM, Kevin Wolf wrote:
>
> The watermark is not some complex computed value, but actually the
> statistic itself. We can get rid of handling a threshold in qemu by just
> signalling "something has changed with this stat".
>
> I'm really not arguing that qemu should do anything complex or even
> define policy. It's just about avoiding polling all the time when
> nothing has changed and polling too late when things are changing quickly.
>
>    
>> Polling is really the right solution.  It gives the management tool
>> ultimate flexibility in tweaking the heuristics as they see fit.
>>      
> Isn't providing this flexibility completely orthogonal to polling vs.
> event-based?
>    

Except then we need to offer a generic statistics mechanism which seems 
like it's going to add a fair bit of complexity.  So far, the only 
argument for it seems to be a misplaced notion that "polling is evil".

Regards,

Anthony Liguori

> Kevin
>