From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37363) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c2jgo-0001kD-7v for qemu-devel@nongnu.org; Fri, 04 Nov 2016 14:58:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c2jgl-0004IR-68 for qemu-devel@nongnu.org; Fri, 04 Nov 2016 14:58:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34254) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1c2jgl-0004HB-0W for qemu-devel@nongnu.org; Fri, 04 Nov 2016 14:58:07 -0400 From: Juan Quintela In-Reply-To: <20161104165933.GA3027@amt.cnet> (Marcelo Tosatti's message of "Fri, 4 Nov 2016 14:59:36 -0200") References: <20161104094322.GA16930@amt.cnet> <20161104165933.GA3027@amt.cnet> Reply-To: quintela@redhat.com Date: Fri, 04 Nov 2016 19:57:59 +0100 Message-ID: <8760o3nkco.fsf@emacs.mitica> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Marcelo Tosatti Cc: kvm@vger.kernel.org, qemu-devel , "Dr. David Alan Gilbert" , Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Eduardo Habkost Marcelo Tosatti wrote: > This patch, relative to pre-copy migration codepath, > measures the time between vm_stop() and pre_save(), > which includes copying the remaining RAM to destination, > and advances the clock by that amount. > > In a VM with 5 seconds downtime, this reduces the guest > clock difference on destination from 5s to 0.2s. > > Tested with Linux and Windows 2012 R2 guests with -cpu XXX,+hv-time. > > Signed-off-by: Marcelo Tosatti > > --- > > v2: use subsection (Juan Quintela) > fix older machine types support > Reviewed-by: Juan Quintela