From mboxrd@z Thu Jan  1 00:00:00 1970
From: Asdo <asdo@shiftmail.org>
Subject: Re: raw disks no longer work in latest kvm (kvm-88 was fine)
Date: Sun, 07 Mar 2010 20:09:26 +0100
Message-ID: <4B93F9E6.2050301@shiftmail.org>
References: <4B92BF97.4040001@nagafix.co.uk>
 <4B92C90B.4030807@msgid.tls.msk.ru> <4B932829.8090503@nagafix.co.uk>
 <4B9372B6.3050408@msgid.tls.msk.ru> <20100307100022.GA23201@infradead.org>
 <4B93A624.8010707@nagafix.co.uk> <4B93AF8A.3070805@nagafix.co.uk>
 <4B93C2F9.7030904@msgid.tls.msk.ru> <4B93DE3F.4090103@nagafix.co.uk>
 <4B93DFF0.5050905@redhat.com> <20100307172151.GA24859@infradead.org>
 <4B93E29E.6090609@redhat.com> <4B93E9EE.6020701@nagafix.co.uk>
 <4B93F4A4.9050003@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Cc: Antoine Martin <antoine@nagafix.co.uk>,
	Christoph Hellwig <hch@infradead.org>,
	Michael Tokarev <mjt@tls.msk.ru>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from mx2.isti.cnr.it ([194.119.192.4]:3433 "EHLO mx2.isti.cnr.it"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1754641Ab0CGTJ1 (ORCPT <rfc822;kvm@vger.kernel.org>);
	Sun, 7 Mar 2010 14:09:27 -0500
Received: from conversionlocal.isti.cnr.it by mx.isti.cnr.it
 (PMDF V6.5-b2 #31825) id <01NKHAMJJBIOBFIGXE@mx.isti.cnr.it> for
 kvm@vger.kernel.org; Sun, 07 Mar 2010 20:09:21 +0100
In-reply-to: <4B93F4A4.9050003@redhat.com>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

Avi Kivity wrote:
> On 03/07/2010 08:01 PM, Antoine Martin wrote:
>>
>> Yes cache=none: "-drive file=./vm/var_fs,if=virtio,cache=none"
>>
>> Side question: this is the right thing to do for raw partitions, right?
>
> The rightest.

Isn't cache=writeback now safe on virtio-blk since 2.6.32?
Doesn't it provide better performances?

Also that looks like a raw file to me, not a partition... do they follow 
the same optimization "rule"?

Thank you