| Posted | Nick | Remark | |
|---|---|---|---|
| #openstack-nova - 2020-09-18 | |||
| 10:41:04 | stephenfin | vs https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L2306-L2309 | |
| 10:41:15 | stephenfin | also not for mdev devices https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L7512 | |
| 10:41:48 | lyarwood | what's the reason for not using the helper with PCI devices? | |
| 10:41:50 | lyarwood | or mdevs? | |
| 10:42:03 | lyarwood | shouldn't the semantics be the same | |
| 10:42:20 | stephenfin | not a clue :) that's what I was thinking but I can't find proof | |
| 10:42:36 | stephenfin | nor can I find proof that what we do for the other cases is even correct | |
| 10:42:43 | sean-k-mooney | so pci device detach was really only done in suspend until recently | |
| 10:42:44 | lyarwood | yeah I would think they should be the same tbh, virtio-blk devices are PCI devices after all | |
| 10:42:52 | lyarwood | oh right | |
| 10:42:57 | stephenfin | for example, we don't pass the live or persistent flags to the attach_device call for PCI devices | |
| 10:42:58 | stephenfin | https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L4425 | |
| 10:43:02 | lyarwood | hotunplug wasn't always a thing with PCI passthrough | |
| 10:43:17 | stephenfin | yet we do for other devices like network interfaces https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L2247 | |
| 10:43:23 | stephenfin | why? I don't know | |
| 10:43:38 | sean-k-mooney | for pci passthough its still not a thing for neutron sriov port it partly worked btu it never freed the devices | |
| 10:43:43 | sean-k-mooney | in the pci tracker | |
| 10:43:51 | lyarwood | kk then that might be why | |
| 10:44:02 | lyarwood | a single call would be enough if the domain was paused | |
| 10:44:08 | lyarwood | and iirc live == running or paused right | |
| 10:44:21 | stephenfin | yeah | |
| 10:44:27 | sean-k-mooney | a paused domian is runnign yes | |
| 10:44:33 | sean-k-mooney | well live | |
| 10:44:34 | stephenfin | I want to replace that with a call to isActive | |
| 10:44:38 | stephenfin | same thing, fwict | |
| 10:44:48 | sean-k-mooney | its still defiend and qemu is running but the cpus are stopped | |
| 10:45:14 | lyarwood | is this all from the dom.xml(PAUSED) patch btw stephenfin ? | |
| 10:45:30 | stephenfin | yup :( I'm way down this rabbit hole now | |
| 10:45:37 | lyarwood | kk | |
| 10:45:48 | lyarwood | well just to confuse you even more | |
| 10:46:03 | lyarwood | https://review.opendev.org/#/c/749929/ is how we should be doing this | |
| 10:46:06 | lyarwood | eventually | |
| 10:46:30 | lyarwood | that's incomplete but events are apparently a better way of checking when things are actually detached | |
| 10:46:48 | stephenfin | oh, very nice | |
| 10:49:53 | lyarwood | urgh I want to rewrite detach_device_with_retry so much in W | |
| 10:51:42 | lyarwood | stephenfin: so sorry I lost track of what the issue is here now | |
| 10:52:31 | stephenfin | The question is whether we should be setting the live parameter here https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L4425 | |
| 10:53:19 | stephenfin | gibi's testing suggests it's not necessary, in which case I guess the question is do we need to be setting it here https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L2247 | |
| 10:54:21 | sean-k-mooney | stephenfin: if we just remove the persistnt domain then this is a moot point | |
| 10:54:29 | stephenfin | true | |
| 10:55:22 | sean-k-mooney | well maybe not | |
| 10:55:27 | sean-k-mooney | we might need to backport something | |
| 10:55:37 | sean-k-mooney | for issue on older branches | |
| 10:55:43 | lyarwood | stephenfin: yeah odd, I wonder if it's something in https://libvirt.org/html/libvirt-libvirt-domain.html#virDomainAttachDeviceFlags that defaults to attaching it to all configs? | |
| 10:56:17 | stephenfin | VIR_DOMAIN_AFFECT_CURRENT sounds reasonable | |
| 10:56:47 | lyarwood | https://github.com/openstack/nova/blob/c49cd3b9669da3f8da377369442bbe749fcb3c13/nova/virt/libvirt/driver.py#L1921 we also do that for disks FWIW | |
| 10:56:52 | lyarwood | provide persistent and live that is | |
| 10:57:22 | sean-k-mooney | lyarwood: ya i was wondering if currently we shoudl jsut set both to true | |
| 10:57:35 | sean-k-mooney | but was not sure if that would fail in some cases | |
| 10:57:56 | stephenfin | Or drop both flags and use VIR_DOMAIN_AFFECT_CURRENT (modify whatever state the instance is currently in) | |
| 11:01:40 | lyarwood | stephenfin: right but we would need to ensure that would attach or detach from both configs at the moment | |
| 11:01:54 | stephenfin | can the two get out of sync? | |
| 11:01:56 | lyarwood | stephenfin: if we dropped the inactive persistent config then yeah we could just use that | |
| 11:01:58 | lyarwood | stephenfin: yup | |
| 11:02:11 | stephenfin | I thought an instance was either persistent or transient | |
| 11:02:24 | stephenfin | *domain | |
| 11:03:45 | openstack | bugzilla.redhat.com bug 1861142 in openstack-nova "[OSP 13.0.z] Unable to detach volume from instance when previously removed from the inactive config" [High,Verified] - Assigned to lyarwood | |
| 11:03:45 | lyarwood | stephenfin: https://bugzilla.redhat.com/show_bug.cgi?id=1861142 for an example btw | |
| 11:05:23 | stephenfin | fun | |
| 11:05:27 | lyarwood | so much | |
| 11:13:58 | sean-k-mooney | how would people feel about backporting droping the persistent domain? is that doable or no? | |
| 11:14:12 | sean-k-mooney | im not sure how that and rolling upgrades would interact | |
| 11:14:15 | stephenfin | let's get it in master before we even think about | |
| 11:14:16 | stephenfin | that | |
| 11:15:06 | sean-k-mooney | ya im just wondering for some of the downstream bugs. | |
| 11:15:20 | sean-k-mooney | although lyarwood you are fixign that bug via the events right | |
| 11:19:51 | lyarwood | We could for new domains | |
| 11:20:03 | lyarwood | we would just need to retain support for persisted domains for a while | |
| 11:20:07 | lyarwood | but that's the same in master | |
| 11:20:22 | lyarwood | actually I don't know if we could ever drop that support really | |
| 11:20:33 | sean-k-mooney | we should be able too | |
| 11:20:37 | lyarwood | unless we wait for major OS changes | |
| 11:20:41 | lyarwood | like bionic to focal | |
| 11:20:44 | lyarwood | that would need LM anyway | |
| 11:21:20 | lyarwood | that would need an upgrade check on the computes | |
| 11:21:42 | sean-k-mooney | so if all new domains are trasiant. and we make all move operations transitant and all hard reboots convert them to transient | |
| 11:21:44 | lyarwood | so ops could be told something like `you're upgrading Nova to a version without support for persistent domains, LM instances from this compute host now before moving` | |
| 11:21:55 | sean-k-mooney | then i think we only need 1 or 2 releases to drop it | |
| 11:22:01 | lyarwood | yeah that's cool | |
| 11:22:26 | sean-k-mooney | we would want a nova status check or something | |
| 11:22:40 | sean-k-mooney | to say hay these vms still need to be moved | |
| 11:23:21 | lyarwood | yup | |
| 11:25:10 | sean-k-mooney | from a down stream persective it woudl be nice if this was in wallaby | |
| 11:25:33 | sean-k-mooney | since the upgrade to wallaby will be an FFU and will involve migrations | |
| 11:25:46 | lyarwood | yup | |
| 11:26:04 | kashyap | sean-k-mooney: I'm on the Focal box you gave me; I'm doing a bunch of tests in it, I hope it won't disappear under my feet? :-) | |
| 11:27:19 | sean-k-mooney | kashyap: not unless you or lyarwood delete it | |
| 11:28:48 | sean-k-mooney | i wont be doing any maintance on it until kolla releases victoria or i hit a kernel issue that requires a reboot | |
| 11:29:01 | kashyap | sean-k-mooney: Ah-ha, thank you | |
| 11:29:02 | sean-k-mooney | its the same cloud i do all my dev on too | |
| 11:29:15 | kashyap | And thanks for doing the gratis maintenance of this cloud for us | |
| 11:29:33 | kashyap | I feel like I should be paying you out in a beverage of your choice, for using your electricity remotely | |
| 11:30:10 | sean-k-mooney | its going to be running anyway | |
| 11:30:29 | sean-k-mooney | at some point im probaly going to redploy a limited third party ci on it again | |
| 11:32:02 | vinay_m | stephenfin : gone through bug comments ,discussed like it would be sphinx version related issue | |
| 11:32:07 | sean-k-mooney | when i do ill proably try and replace fort nebula for multi numa testing of the whitebox plugin | |
| 11:33:28 | vinay_m | i would like to explore how a search ref link working ,added in nova/doc/source/index.rst , how can i ? | |
| 11:34:25 | sean-k-mooney | vinay_m: you can propose a patch via gerrit and the docs job will render a preview sight | |
| 11:34:31 | sean-k-mooney | you can also build the docs locally | |
| 11:34:35 | sean-k-mooney | using tox | |