| Posted | Nick | Remark | |
|---|---|---|---|
| #openstack-nova - 2018-01-11 | |||
| 14:01:13 | efried | gibi bauzas Somebody oughtta do it. The time is now :) | |
| 14:03:01 | mdbooth | bauzas: I really think it's only volumes. | |
| 14:03:30 | mdbooth | The others we're just adding devices to the guest. The different with volumes and now vgpus is that we're reconfiguring the host. | |
| 14:03:46 | mdbooth | So we're doing _get_guest_xml() and it has surprising side-effects | |
| 14:03:48 | bauzas | mdbooth: https://github.com/openstack/nova/blob/master/nova/virt/libvirt/driver.py#L4882 ? | |
| 14:04:09 | mdbooth | bauzas: Yeah, that's just pulling them out of the instance. | |
| 14:04:16 | mdbooth | IIUC they've already been allocated elsewhere. | |
| 14:04:17 | bauzas | mdbooth: what's the difference between attaching a PCI device or a mediated device ? | |
| 14:04:40 | mdbooth | Because you're not creating the pci device, or doing any kind of 'scheduling' | |
| 14:05:13 | mdbooth | You're not calling _get_guest_xml() and suddenly you've created a new pci device | |
| 14:05:59 | mdbooth | Anyway, I agree with your prioritisation. That said, I really don't like it about volumes, and I'm uncomfortable adding more of it. | |
| 14:06:03 | bauzas | mdbooth: but the allocation was made way earlier :) | |
| 14:06:12 | bauzas | for the VGPU | |
| 14:06:35 | bauzas | if you go to that compute, that's because it has free space for a vGPU | |
| 14:06:45 | bauzas | because placement told you | |
| 14:06:58 | bauzas | exactly like NUMA things | |
| 14:07:12 | bauzas | the scheduler or placement won't know which specific device you're assigned | |
| 14:07:19 | bauzas | but it will know there is room for you | |
| 14:07:39 | bauzas | in theory, you should never raise the exception I added | |
| 14:08:47 | mdbooth | bauzas: There's also the case of recreating the domain xml with existing mdevs. | |
| 14:09:35 | mdbooth | Although perhaps that doesn't matter as long as we're absolutely certain the domain isn't running. | |
| 14:09:58 | mdbooth | But again that's an embedded assumption which makes everything harder to understand. | |
| 14:10:32 | bauzas | mdbooth: the problem is that the XML isn't persisted when you stop the instance | |
| 14:10:38 | bauzas | I mean in Nova | |
| 14:10:46 | bauzas | that's surprising to me | |
| 14:10:57 | bauzas | we regenerate the XML when we start again the instance | |
| 14:11:02 | bauzas | while it's already been defined ! | |
| 14:11:23 | bauzas | mdbooth: any idea you know why ? | |
| 14:11:25 | mdbooth | Yeah, that's... suboptimal. | |
| 14:11:34 | bauzas | that's rather errorprone | |
| 14:11:52 | mdbooth | A legacy design choice that Nova is the ultimate source of truth. It means we lose stuff like device ordering and address assignments. | |
| 14:13:04 | bauzas | I can understand the reasoning | |
| 14:13:12 | bauzas | but then, you somehow need to persist that | |
| 14:13:19 | bauzas | and rather not rebuilding it | |
| 14:13:23 | bauzas | but that's MHO | |
| 14:13:34 | bauzas | and I'm possibly missing some design choices | |
| 14:14:28 | artom | It may have come from the need to support other drivers? | |
| 14:14:35 | artom | Who don't necessarily keep state like libvirt does? | |
| 14:14:50 | mdbooth | artom: This is an internal libvirt driver detail. | |
| 14:15:10 | bauzas | anyway | |
| 14:15:36 | bauzas | I have some stupid formatting to do, because pci names are different from filesystem | |
| 14:15:47 | bauzas | I mean pci names in libvirt | |
| 14:15:53 | bauzas | grrrr | |
| 14:15:56 | mdbooth | bauzas: I agree that moving that stuff is less important, though. | |
| 14:16:21 | mdbooth | I think where we differ is much less important we think it is ;) | |
| 14:16:37 | cdent | "source of truth" is definitely a common issue | |
| 14:17:09 | bauzas | distributed systems is a NP-problem by definition | |
| 14:17:18 | bauzas | so I'm not afraid | |
| 14:20:13 | mdbooth | bauzas: The other things are bugs, anyway. This is an issue of ongoing maintainability. | |
| 14:21:15 | kashyap | stephenfin: Hey, have you setup DevStack lately on an older branch (Mitaka) on CentOS? | |
| 14:21:41 | stephenfin | kashyap: Newton is as far back I've gone in a while, I think | |
| 14:21:42 | kashyap | I don't see Mitaka branch in DevStack, do they "delete" the older branches? | |
| 14:21:46 | stephenfin | and that was before it was EOL | |
| 14:21:56 | stephenfin | I guess they do. Look for the mitaka-eol tag | |
| 14:22:22 | kashyap | stack@devstack-centos ~/src/cloud/devstack (master) $ git branch -a | grep -i mitaka | |
| 14:22:25 | kashyap | stack@devstack-centos ~/src/cloud/devstack (master) $ echo $? | |
| 14:22:28 | kashyap | 1 | |
| 14:22:42 | stephenfin | git tag -a | grep -i mitaka | |
| 14:23:01 | kashyap | s/-a/-l/ | |
| 14:23:25 | stephenfin | Indeed | |
| 14:23:26 | kashyap | Yep, could fetch from the tag. Thx. | |
| 14:23:35 | stephenfin | Once you've that checked out, you'll also want to modify the branches that are checked out, e.g. https://gist.github.com/stephenfin/d1c000f7e52ff181c4673322b28eaf47#file-local-conf-L71-L81https://gist.github.com/stephenfin/d1c000f7e52ff181c4673322b28eaf47#file-local-conf-L71-L81 | |
| 14:23:46 | stephenfin | I guess they should all be 'mitaka-eol' | |
| 14:24:25 | kashyap | stephenfin: Yeah, my attempt on Fedora for Mitaka failed | |
| 14:25:07 | kashyap | Failed as in, the libvirt-python wonkiness: http://paste.openstack.org/show/642707/ | |
| 14:25:08 | stephenfin | Aye, an LTS distro is probably the way to go. Guess either Ubuntu 14.04 or CentOS 7.4 is your best bet | |
| 14:25:29 | kashyap | It's missing two of the events, when building libvirt-python | |
| 14:25:59 | kashyap | Didn't wanted to duke around there, so just went w/ CentOS. Let's see how that goes. | |
| 14:27:12 | kashyap | stephenfin: I used to use -- https://kashyapc.fedorapeople.org/virt/openstack/Minimal-DevStack-local.conf | |
| 14:27:26 | kashyap | I know it could be improved (Neutron is now default, etc). | |
| 14:50:09 | openstackgerrit | Lee Yarwood proposed openstack/nova master: libvirt: Collocate encryptor and volume driver calls https://review.openstack.org/460243 | |
| 14:50:10 | openstackgerrit | Lee Yarwood proposed openstack/nova master: WIP libvirt: QEMU native LUKS decryption for volumes https://review.openstack.org/523958 | |
| 14:50:10 | openstackgerrit | Lee Yarwood proposed openstack/nova master: libvirt: Introduce disk encryption config classes https://review.openstack.org/464008 | |
| 15:03:13 | mriedem | oops, totally forgot about the team meeting | |
| 15:03:51 | mriedem | gibi: thanks for running that | |
| 15:05:04 | openstackgerrit | sahid proposed openstack/nova master: libvirt: slow live-migration to ensure network is ready https://review.openstack.org/497457 | |
| 15:05:05 | gibi | mriedem: no problem, I was not prepared but I could run it | |
| 15:10:30 | efried | Hi cores, would anyone be willing to look at the first two patches for the PowerVM integration bp? https://review.openstack.org/#/q/status:open+project:openstack/nova+branch:master+topic:bp/powervm-nova-it-compute-driver | |
| 15:11:00 | efried | stephenfin gibi bauzas perhaps if you have time? | |
| 15:11:43 | stephenfin | efried: I've been meaning to review the OVS VIF one, but I'll have to leave the storage patches to someone else | |
| 15:11:45 | bauzas | efried: I'm still rushing on my feature branch :/ | |
| 15:11:52 | bauzas | efried: blame mdbooth | |
| 15:12:09 | mdbooth | bauzas: Sorry :P | |
| 15:12:52 | bauzas | mdbooth: no worries, you just owe me a beer :p | |
| 15:12:58 | bauzas | et voila! | |
| 15:13:16 | bauzas | interesting, creating a new mdev even if you have a kernel race works | |
| 15:13:25 | bauzas | that's awesome news | |
| 15:13:37 | bauzas | since the mdev is *really* created, you can ask libvirt to use it | |
| 15:13:46 | bauzas | even if libvirt isn't able to show it per its API | |
| 15:13:53 | bauzas | amazing | |
| 15:14:10 | bauzas | so, one big caveat isn't really a big deal and not requiring a separate change | |
| 15:14:14 | bauzas | just docs | |
| 15:14:22 | bauzas | huzzah | |
| 15:14:24 | efried | stephenfin Thanks, anything helps. TBH, there's not a lot of storage (or network) understanding required for these. The guts are in the pypowervm lib; these patches are really just translating the nova-ese to powervm-ese. | |
| 15:19:14 | mriedem | stephenfin: do you see anything obviously wrong with https://review.openstack.org/#/c/532689/ ? i ran it last night through the experimental queue but results were never posted back on the patch | |
| 15:20:05 | mriedem | i can see it queued up in the experimental queue in zuul right now | |
| 15:22:24 | mriedem | gmann: https://review.openstack.org/#/c/330406/85/nova/api/openstack/compute/migrations.py@119 | |
| 15:22:32 | mriedem | we have 2.0 and 2.1 all over the API, it doesn't seem to make a difference | |
| 15:24:07 | openstackgerrit | sahid proposed openstack/nova master: hardware: only take into account small pages https://review.openstack.org/532168 | |
| 15:26:57 | hongbin | mrodden: mlavalle : want to make a call on the full substring or partial substring debate https://review.openstack.org/#/c/521683/ ? | |