From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59216) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bwUdm-0006qM-0H for qemu-devel@nongnu.org; Tue, 18 Oct 2016 09:41:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bwUdh-0008Hd-5Z for qemu-devel@nongnu.org; Tue, 18 Oct 2016 09:41:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41598) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1bwUdh-0008HT-0B for qemu-devel@nongnu.org; Tue, 18 Oct 2016 09:41:09 -0400 References: <20161014212031.GQ3275@thinpad.lan.raisama.net> <20161017094708.GB31691@amt.cnet> <20161017145008.GA2307@potion> <72b8c6b3-f08a-735a-e283-99d0195dcf7d@redhat.com> <20161017211101.GD3275@thinpad.lan.raisama.net> <20161017235846.GA22657@amt.cnet> From: Paolo Bonzini Message-ID: <74794dbf-a904-54b9-315f-1bc385a959ba@redhat.com> Date: Tue, 18 Oct 2016 15:41:03 +0200 MIME-Version: 1.0 In-Reply-To: <20161017235846.GA22657@amt.cnet> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] invtsc + migration + TSC scaling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Marcelo Tosatti , Eduardo Habkost Cc: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , qemu-devel@nongnu.org, kvm@vger.kernel.org On 18/10/2016 01:58, Marcelo Tosatti wrote: > > We should also blacklist the TSC deadline timer when invtsc is not > > available. > > Actually, a nicer fix would be to check the different > frequencies and scale the deadline relative to the difference. You cannot know what exactly the guest was thinking when it set the TSC deadline. Perhaps it wanted an interrupt when the TSC was exactly 9876543210. Paolo