From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37082) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YNKjJ-0007oJ-Qw for qemu-devel@nongnu.org; Mon, 16 Feb 2015 07:24:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YNKjF-0006F6-If for qemu-devel@nongnu.org; Mon, 16 Feb 2015 07:24:49 -0500 Received: from mail-wi0-x235.google.com ([2a00:1450:400c:c05::235]:45785) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YNKjF-0006Et-Am for qemu-devel@nongnu.org; Mon, 16 Feb 2015 07:24:45 -0500 Received: by mail-wi0-f181.google.com with SMTP id r20so25870464wiv.2 for ; Mon, 16 Feb 2015 04:24:44 -0800 (PST) Sender: Paolo Bonzini Message-ID: <54E1E188.4050407@redhat.com> Date: Mon, 16 Feb 2015 13:24:40 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <54E0E974.4010301@profihost.ag> In-Reply-To: <54E0E974.4010301@profihost.ag> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Priebe , qemu-devel On 15/02/2015 19:46, Stefan Priebe wrote: > > while i get a constant random 4k i/o write speed of 20.000 iops with > qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between > 500 iops and 15.000 iop/s). > > If i use virtio instead of virtio-scsi speed is the same between 2.2 and > 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Paolo