From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: TODO list for qemu+KVM networking performance v2
Date: Wed, 10 Jun 2009 19:08:49 +0300
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Cc: Rusty Russell <rusty@rustcorp.com.au>, dlaor@redhat.com,
	virtualization@lists.linux-foundation.org,
	Chris Wright <chrisw@redhat.com>,
	Mark McLoughlin <markmc@redhat.com>, kvm@vger.kernel.org,
	Brian Stein <bstein@redhat.com>,
	Herbert Xu <herbert.xu@redhat.com>, Dor Laor <dor@redhat.com>,
	Yaron Haviv <yaronh@voltaire.com>,
	Shahar Klein <shahark@voltaire.com>,
	Anthony Liguori <aliguori@us.ibm.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
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Michael S. Tsirkin wrote:
> On Wed, Jun 10, 2009 at 06:18:01PM +0300, Avi Kivity wrote:
>   
>> Michael S. Tsirkin wrote:
>>     
>>> But I don't understand how aio will make implementing it easier -
>>> or are you merely saying that it will make it worthwhile?
>>>   
>>>       
>> If you have aio, the the NIC and the guest proceed in parallel.  If the  
>> guest is faster (likely), then when it sends the next packet it will see  
>> that interrupts are disabled and not notify again.  Once aio complete we  
>> can recheck the queue; if it's empty we reenable notifications.  If  
>> there's still stuff in it we submit it with notifications disabled.
>>     
>
> So you are saying that with aio we won't need this optimization at all?
> I guess it's late in the day, and my mind is fuzzy...
>   

No, I'm saying with aio the optimization becomes worthwhile.  But I 
joined late in the thread so we may be talking about different things.

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