From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55263) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ViOFT-0006c1-P0 for qemu-devel@nongnu.org; Mon, 18 Nov 2013 07:48:24 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ViOFL-0004ZH-Bv for qemu-devel@nongnu.org; Mon, 18 Nov 2013 07:48:15 -0500 Received: from mx.ipv6.kamp.de ([2a02:248:0:51::16]:37790 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ViOFL-0004Yq-10 for qemu-devel@nongnu.org; Mon, 18 Nov 2013 07:48:07 -0500 Message-ID: <528A0C84.6080809@kamp.de> Date: Mon, 18 Nov 2013 13:48:04 +0100 From: Peter Lieven MIME-Version: 1.0 References: <1382599289-9503-1-git-send-email-pl@kamp.de> <5268E4EF.3090007@redhat.com> In-Reply-To: <5268E4EF.3090007@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RESEND][PATCH 1.7] migration: drop MADVISE_DONT_NEED for incoming zero pages List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: haoyu.zhang@huawei.com, xiaoguangrong@linux.vnet.ibm.com, qemu-devel@nongnu.org, afaerber@suse.de, quintela@redhat.com On 24.10.2013 11:14, Paolo Bonzini wrote: > Il 24/10/2013 08:21, Peter Lieven ha scritto: >> Additionally we memmap target memory so it is essentially >> zero initialized (except for e.g. option roms and bios which are loaded >> into target memory although they shouldn't). >> >> It was reported recently that this madvise causes a performance degradation >> in some situations. As the madvise should only be called rarely and if it's called >> it is likely on a busy page (it was non-zero and changed to zero during migration) >> drop it completely. > Tagging this patch for 1.7. has this been merged? Peter