From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43411) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XOsYE-0001mG-W3 for qemu-devel@nongnu.org; Tue, 02 Sep 2014 14:11:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XOsY5-0004hE-SC for qemu-devel@nongnu.org; Tue, 02 Sep 2014 14:11:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:10021) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XOsY5-0004gO-KZ for qemu-devel@nongnu.org; Tue, 02 Sep 2014 14:11:21 -0400 Date: Tue, 2 Sep 2014 23:41:13 +0530 From: Amit Shah Message-ID: <20140902181113.GF30168@grmbl.mre> References: <201408291545282753855@sangfor.com> <20140829143849.GA8909@grmbl.mre> <201409012038178763909@sangfor.com> <201409012052442706397@sangfor.com> <20140902063637.GG14171@grmbl.mre> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [question] virtio-blk performance degradationhappened with virito-serial List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Andrey Korolyov Cc: Zhang Haoyu , qemu-devel , kvm On (Tue) 02 Sep 2014 [22:05:45], Andrey Korolyov wrote: > Can confirm serious degradation comparing to the 1.1 with regular > serial output - I am able to hang VM forever after some tens of > seconds after continuously printing dmest to the ttyS0. VM just ate > all available CPU quota during test and hanged over some tens of > seconds, not even responding to regular pings and progressively > raising CPU consumption up to the limit. Entirely different to what's being discussed here. You're observing slowdown with ttyS0 in the guest -- the isa-serial device. This thread is discussing virtio-blk and virtio-serial. Amit