From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39292) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UygXM-0003nk-RI for qemu-devel@nongnu.org; Mon, 15 Jul 2013 07:01:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UygXI-0005xF-6x for qemu-devel@nongnu.org; Mon, 15 Jul 2013 07:01:48 -0400 Received: from goliath.siemens.de ([192.35.17.28]:30178) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UygXH-0005x3-UC for qemu-devel@nongnu.org; Mon, 15 Jul 2013 07:01:44 -0400 Message-ID: <51E3D690.6070208@siemens.com> Date: Mon, 15 Jul 2013 13:01:36 +0200 From: Jan Kiszka MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Performance regression "ioport: Switch dispatching to memory core layer" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: Paolo Bonzini , qemu-devel On 2013-07-15 12:52, Stefan Hajnoczi wrote: > The following qemu.git commit adds a ~2 minute regression in boot time > to a x86_64 live CD: > > commit b40acf99bef69fa8ab0f9092ff162fde945eec12 > Author: Jan Kiszka > Date: Mon Jun 24 10:45:09 2013 +0200 > > ioport: Switch dispatching to memory core layer > > After the ISOLINUX menu, the display goes white and sits there for about > 2 minutes on my laptop before the usual Linux boot screen appears. > > $ qemu-system-x86_64 -enable-kvm -cpu host -m 1024 -cdrom ~/iso/livecd.iso > > The parent commit immediately goes to the usual boot screen after > ISOLINUX. Unfortunately I don't have a ISO download link for the live > CD. Can you share it otherwise (before I spend time on recreating something that does not trigger it)? > > Any ideas? What does perf say during that time? What ftrace regarding the port numbers and access types? Jan -- Siemens AG, Corporate Technology, CT RTC ITP SES-DE Corporate Competence Center Embedded Linux