From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1O6kUF-0007If-9k
	for qemu-devel@nongnu.org; Tue, 27 Apr 2010 09:06:03 -0400
Received: from [140.186.70.92] (port=39681 helo=eggs.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1O6kUE-0007I9-5e
	for qemu-devel@nongnu.org; Tue, 27 Apr 2010 09:06:02 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69)
	(envelope-from <gleb@redhat.com>) id 1O6kUC-0008Bw-LZ
	for qemu-devel@nongnu.org; Tue, 27 Apr 2010 09:06:01 -0400
Received: from mx1.redhat.com ([209.132.183.28]:54672)
	by eggs.gnu.org with esmtp (Exim 4.69)
	(envelope-from <gleb@redhat.com>) id 1O6kUC-0008Bj-7g
	for qemu-devel@nongnu.org; Tue, 27 Apr 2010 09:06:00 -0400
Date: Tue, 27 Apr 2010 16:05:56 +0300
From: Gleb Natapov <gleb@redhat.com>
Message-ID: <20100427130556.GH10044@redhat.com>
References: <20100426172634.GC15278@x200.localdomain>
	<4BD5D28C.7080700@codemonkey.ws>
	<20100426221258.GH15278@x200.localdomain>
	<4BD61584.9080208@codemonkey.ws>
	<20100427111140.GF10044@redhat.com>
	<4BD6DFD2.7050509@codemonkey.ws>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <4BD6DFD2.7050509@codemonkey.ws>
Subject: [Qemu-devel] Re: KVM call agenda for Apr 27
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Chris Wright <chrisw@redhat.com>, qemu-devel@nongnu.org, kvm@vger.kernel.org

On Tue, Apr 27, 2010 at 08:00:02AM -0500, Anthony Liguori wrote:
> On 04/27/2010 06:11 AM, Gleb Natapov wrote:
> >Network cards have low number of rx/tx buffers interrupt. This is also
> >heuristic. Do you think driver should poll for this event instead and
> >NIC designers just wasted their time designing the feature?
> 
> I don't see how the two cases are at all similar.
> 
They are the same. They send notification when resource is low.

> More importantly, I don't see what the burden is of polling when
> you're talking about a very unusual statistic that has a very
> limited use case.
> 
Poll is the wrong answer. Always. The statistic is very common and has
wide use case unless you have unlimited storage.


--
			Gleb.