Re: [openstack-dev] [nova] Feature about QEMU Assisted online-extend volume
On 29 March 2014 02:49, Zhangleiqiang (Trump) zhangleiqi...@huawei.com wrote: Hi, Duncan: Thanks for your advice. About the summit session you mentioned, what things can I do for it ? If you (or a colleague who can speak on your behalf) is going to the summit, then go to 'http://summit.openstack.org/' and click 'suggest session'. Note that you will need somebody to present / discuss / defend the proposal at the summit, it rarely goes well if the proposer isn't present. Having a detailed blueprint available before the summit also helps, in this case it looks like that is covered. ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [nova] Feature about QEMU Assisted online-extend volume
Hi, Duncan: Thanks for your advice. About the summit session you mentioned, what things can I do for it ? -- zhangleiqiang (Trump) Best Regards -Original Message- From: Duncan Thomas [mailto:duncan.tho...@gmail.com] Sent: Friday, March 28, 2014 12:43 AM To: OpenStack Development Mailing List (not for usage questions) Subject: Re: [openstack-dev] [nova] Feature about QEMU Assisted online-extend volume It sounds like a useful feature, and there are a growing number of touch points for libvirt assisted cinder features. A summit session to discuss how that interface should work (hopefully get a few nova folks there as well, the interface has two ends) might be a good idea On 27 March 2014 16:15, Trump.Zhang zhangleiqi...@gmail.com wrote: Online-extend volume feature aims to extend a cinder volume which is in-use, and make the corresponding disk in instance extend without stop the instance. The background is that, John Griffith has proposed a BP ([1]) aimed to provide an cinder extension to enable extend of in-use/attached volumes. After discussing with Paul Marshall, the assignee of this BP, he only focus on OpenVZ driver currently, so I want to take the work of libvirt/qemu based on his current work. A volume can be extended or not is determined by Cinder. However, if we want the capacity of corresponding disk in instance extends, Nova must be involved. Libvirt provides block_resize interface for this situation. For QEMU, the internal workflow for block_resize as follows: 1) Drain all IO of this disk from instance 2) If the backend of disk is a normal file, such as raw, qcow2, etc, qemu will do the *extend* work 3) If the backend of disk is block device, qemu will first judge if there is enough free space on the device, if only so, it will do the *extend* work. So I think the online-extend volume will need QEMU Assisted, which is simlar to BP [2]. Do you think we should introduce this feature? [1] https://blueprints.launchpad.net/cinder/+spec/inuse-extend-volume-exte nsion [2] https://blueprints.launchpad.net/nova/+spec/qemu-assisted-snapshots ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev -- Duncan Thomas ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
[openstack-dev] [nova] Feature about QEMU Assisted online-extend volume
Online-extend volume feature aims to extend a cinder volume which is in-use, and make the corresponding disk in instance extend without stop the instance. The background is that, John Griffith has proposed a BP ([1]) aimed to provide an cinder extension to enable extend of in-use/attached volumes. After discussing with Paul Marshall, the assignee of this BP, he only focus on OpenVZ driver currently, so I want to take the work of libvirt/qemu based on his current work. A volume can be extended or not is determined by Cinder. However, if we want the capacity of corresponding disk in instance extends, Nova must be involved. Libvirt provides block_resize interface for this situation. For QEMU, the internal workflow for block_resize as follows: 1) Drain all IO of this disk from instance 2) If the backend of disk is a normal file, such as raw, qcow2, etc, qemu will do the *extend* work 3) If the backend of disk is block device, qemu will first judge if there is enough free space on the device, if only so, it will do the *extend* work. So I think the online-extend volume will need QEMU Assisted, which is simlar to BP [2]. Do you think we should introduce this feature? [1] https://blueprints.launchpad.net/cinder/+spec/inuse-extend-volume-extension [2] https://blueprints.launchpad.net/nova/+spec/qemu-assisted-snapshots ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [nova] Feature about QEMU Assisted online-extend volume
It sounds like a useful feature, and there are a growing number of touch points for libvirt assisted cinder features. A summit session to discuss how that interface should work (hopefully get a few nova folks there as well, the interface has two ends) might be a good idea On 27 March 2014 16:15, Trump.Zhang zhangleiqi...@gmail.com wrote: Online-extend volume feature aims to extend a cinder volume which is in-use, and make the corresponding disk in instance extend without stop the instance. The background is that, John Griffith has proposed a BP ([1]) aimed to provide an cinder extension to enable extend of in-use/attached volumes. After discussing with Paul Marshall, the assignee of this BP, he only focus on OpenVZ driver currently, so I want to take the work of libvirt/qemu based on his current work. A volume can be extended or not is determined by Cinder. However, if we want the capacity of corresponding disk in instance extends, Nova must be involved. Libvirt provides block_resize interface for this situation. For QEMU, the internal workflow for block_resize as follows: 1) Drain all IO of this disk from instance 2) If the backend of disk is a normal file, such as raw, qcow2, etc, qemu will do the *extend* work 3) If the backend of disk is block device, qemu will first judge if there is enough free space on the device, if only so, it will do the *extend* work. So I think the online-extend volume will need QEMU Assisted, which is simlar to BP [2]. Do you think we should introduce this feature? [1] https://blueprints.launchpad.net/cinder/+spec/inuse-extend-volume-extension [2] https://blueprints.launchpad.net/nova/+spec/qemu-assisted-snapshots ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev -- Duncan Thomas ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
