From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60711) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W2xQy-0007eb-Px for qemu-devel@nongnu.org; Tue, 14 Jan 2014 01:25:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W2xQu-0007I8-6t for qemu-devel@nongnu.org; Tue, 14 Jan 2014 01:25:08 -0500 Received: from mail-gg0-f175.google.com ([209.85.161.175]:40433) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W2xQu-0007Fh-3m for qemu-devel@nongnu.org; Tue, 14 Jan 2014 01:25:04 -0500 Received: by mail-gg0-f175.google.com with SMTP id c2so1730379ggn.34 for ; Mon, 13 Jan 2014 22:25:03 -0800 (PST) Message-ID: <52D4D83B.4040803@inktank.com> Date: Mon, 13 Jan 2014 22:24:59 -0800 From: Josh Durgin MIME-Version: 1.0 References: <20140108044407.GG30570@stefanha-thinkpad.redhat.com> In-Reply-To: Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] =?gb2312?b?u9i4tKO6ILvYuLSjuiC72Li0o7ogIHFlbXUgdm0g?= =?gb2312?b?YmlnIG5ldHdvcmsgbGF0ZW5jeSB3aGVuIG1ldCBoZWF2eSBpbw==?= List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi , =?GB2312?B?0rbJ3Oih?= Cc: qemu-devel On 01/12/2014 06:39 PM, Stefan Hajnoczi wrote: > On Fri, Jan 10, 2014 at 11:50 AM, Ò¶ÉÜè¡ wrote: > > Please use Reply-all to keep the CC list in tact. That way the > conversation stays on the mailing list and others can participate. > >>> Is the sum of guests' RAM less than the total physical RAM on the host >> The host run 3 vms, each vm use one vcpu core and 1G ram. >> # free -m >> >> total used free shared buffers cached >> >> Mem: 32242 4808 27434 0 278 2058 >> >> -/+ buffers/cache: 2471 29771 >> >> Swap: 4095 0 4095 >> >> >> The host has 8 cores. >> # cat /proc/cpuinfo | grep processor >> processor : 0 >> processor : 1 >> processor : 2 >> processor : 3 >> processor : 4 >> processor : 5 >> processor : 6 >> processor : 7 >> >> so, both of two question's answer is 'yes'. >> When I runing random write test, the host use 0 swap. > > Great. That means the host is not overcommitted. > > It's likely that the problem is a bug in QEMU's rbd driver or librados. > > Josh: Perhaps something you're interested in looking into? Yes, thanks for bringing it to my attention. It does sound like a bug in QEMU's rbd driver or ceph's userspace libraries. Could you share what version of librbd you're using, and your /etc/ceph/ceph.conf? Thanks, Josh