From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:48861) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UBQiH-0005XZ-OT for qemu-devel@nongnu.org; Fri, 01 Mar 2013 09:13:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UBQiB-00027L-M6 for qemu-devel@nongnu.org; Fri, 01 Mar 2013 09:13:29 -0500 Received: from ssl.dlhnet.de ([91.198.192.8]:55889 helo=ssl.dlh.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UBQiB-000279-Fx for qemu-devel@nongnu.org; Fri, 01 Mar 2013 09:13:23 -0500 Message-ID: <5130B789.7050709@dlhnet.de> Date: Fri, 01 Mar 2013 15:13:29 +0100 From: Peter Lieven MIME-Version: 1.0 References: <5130ADC0.9070402@dlhnet.de> <5130B29C.3060301@redhat.com> <5130B5D8.7030308@dlhnet.de> <5130B677.1060604@redhat.com> In-Reply-To: <5130B677.1060604@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] migration: use XBZRLE only after bulk stage List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: Orit Wasserman , "qemu-devel@nongnu.org" , Paolo Bonzini On 01.03.2013 15:08, Eric Blake wrote: > On 03/01/2013 07:06 AM, Peter Lieven wrote: >>> Do you have any benchmark numbers? At any rate, the explanation seems >>> sound, so a benchmark should show this. >> >> Do you have a particular test pattern in mind? If there is nothing going on >> in the VM XBZRLE will not be better than normal copy at all. >> >> Otherwise you will have N xbzrle misses and 0 xbzrle pages without the >> patch >> and 0 xbzrle misses and 0 xbzrle pages with the patch. > > How about a migration of a guest running the synthetic r/w load > generator in docs/xbzrle.txt? > Good idea. I will leave max downtime and bandwidth at default values. Would you be happy with 1GB vRAM and 256MB page cache? Peter