From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42744) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YpL9h-00042w-Bh for qemu-devel@nongnu.org; Mon, 04 May 2015 14:31:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YpL9c-0004sX-83 for qemu-devel@nongnu.org; Mon, 04 May 2015 14:31:49 -0400 Received: from fmvm01.lax10.vpls.net ([209.11.253.20]:58201) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YpL9c-0004qz-0C for qemu-devel@nongnu.org; Mon, 04 May 2015 14:31:44 -0400 Date: Mon, 4 May 2015 21:34:21 +0300 From: Fahri Cihan Demirci Message-ID: <20150504183420.GA3127@caesium> References: <20150504162442.GA12825@francium.user.ytu.skyatlas.com> <1954990735.5679237.1430761748082.JavaMail.zimbra@oxygem.tv> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1954990735.5679237.1430761748082.JavaMail.zimbra@oxygem.tv> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] VCPU Hot-Unplug Feature List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexandre DERUMIER Cc: qemu-devel Hello Alexandre, Thank you for your response. I came upon that patch on the Libvirt mailin= g list, too. However, the following comment makes me think that it's not = likely to be merged: https://www.redhat.com/archives/libvir-list/2015-February/msg00415.html Also, later in the thread, the author of the patch seems to confirm that = the plan for hotplug in QEMU is not compatible with that patch: https://www.redhat.com/archives/libvir-list/2015-March/msg01169.html So, I think Libvirt developers have decided to wait until there is a gene= ralized groundwork for VCPU hot-unplug in the QEMU code base. That's why = I decided to inquire and offer help for QEMU developers, since the ball s= eems to be in their court now. Thanks a lot for your time. On Mon, May 04, 2015 at 07:49:08PM +0200, Alexandre DERUMIER wrote: > Hi, >=20 > they are a lot of patches sent on the mailing list recently, >=20 > cpu hotplug|unplug with device_add|del >=20 > https://www.redhat.com/archives/libvir-list/2015-February/msg00084.html >=20 >=20 >=20 > ----- Mail original ----- > De: "Fahri Cihan Demirci" > =C0: "qemu-devel" > Envoy=E9: Lundi 4 Mai 2015 18:24:43 > Objet: [Qemu-devel] VCPU Hot-Unplug Feature >=20 > Hello,=20 >=20 > We are interested in being able to remove a VCPU from an active Libvirt= domain running under QEMU/KVM. However, currently that does not seem to = be possible because QEMU does not provide an interface for hot-unplugging= a VCPU. The corresponding feature page [1] on the QEMU wiki mentions the= cpu-add interface and the generalized device add/del interface. So, my q= uestion is, is there someone working on a cpu-remove interface or making = progress in the generalized device add/del interface to hot-unplug VCPUS?= If you are in any way interested in or planning such a feature, we may p= rovide feedback, testing or help in the development effort. Any other inp= ut, guidance or corrections would be also most welcome. Thank you.=20 >=20 > [1] http://wiki.qemu.org/Features/CPUHotplug=20 >=20 >=20 > Best regards,=20 > Fahri Cihan Demirci=20