From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:48331) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RanJ1-00031q-AM for qemu-devel@nongnu.org; Wed, 14 Dec 2011 06:47:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RanIx-0007M0-5l for qemu-devel@nongnu.org; Wed, 14 Dec 2011 06:47:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:29497) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RanIw-0007Lr-Tj for qemu-devel@nongnu.org; Wed, 14 Dec 2011 06:47:23 -0500 Message-ID: <4EE88CC3.7090903@redhat.com> Date: Wed, 14 Dec 2011 12:47:15 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1323779840-4235-1-git-send-email-pbonzini@redhat.com> <4EE884BD.4090808@redhat.com> In-Reply-To: <4EE884BD.4090808@redhat.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 00/17] Support mismatched host and guest logical block sizes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: Christoph Hellwig , qemu-devel@nongnu.org, Stefan Hajnoczi On 12/14/2011 12:13 PM, Kevin Wolf wrote: > As we discussed before, the really interesting point here is defaults, > and whatever you choose to do is wrong in some respect. > > So it looks like you chose to make the virtual device default to the > host block size. ... wait wait, I default to 512. :) Here is the rationale. 512-over-4k may be slow, but is safe (but it is not slow if you align partitions properly). 4k-over-512 is unsafe. So, defaulting to 512 seemed the right thing after all. Paolo