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#openstack-nova - 2018-06-22
18:37:03 dansmith right, so at the end of the day, you're going to generate some new xml document which contains a subset of the things you need and on the source have to parse that expected structure and pick out the pieces you want
18:37:19 artom 'zactly
18:37:29 dansmith which you could do super hackily by just grabbing the root of any subtree and yank it straight into the xml you're sending to the other side in migrate,
18:37:47 dansmith but that would be pretty trusting of the other side, and wouldn't have a very high confidence that you're generating valid xml
18:37:58 dansmith and if you're going to inspect every piece of it to transplant it,
18:38:14 dansmith I kinda think that you might as well have used our own objects for that transport
18:38:32 artom Yeah, good point
18:38:41 dansmith instead of using another complex structure that kinda looks like libvirt's but isn't exactly, and doesn't have the rest of the ingrained patterns our devs are used to
18:39:10 dansmith so I dunno.. if it was one blob that was <all_numa_stuff> ... </> then it'd be a little more sane to just drop it in (maybe), but since it's not...
18:39:36 artom That being said, it's XML by the destination for the destination
18:39:53 dansmith it is, but it's yanked into a larger xml doc the destination hasn't seen yet
18:39:59 artom Does it really make sense for the source to do anything other than, as you said, grab the subtree and stick it in?
18:40:06 artom Also true
18:40:28 dansmith well, the source will have to merge or replace the vcpu elements, for example
18:40:53 dansmith if there was a non-numa-related attribute that the destination doesn't know how to calculate, for example,
18:41:18 dansmith then the source would have to reason about the mergeification of the numa-related fragments we got from the destination, in context of the other non-numa-related ones already in the xml
18:41:20 artom Replace, I would think - the instance numa topology hasn't changed, so for example '<vcpupin vcpu="0"' should not change
18:41:45 dansmith which may not happen now or later, but it supports the "just dropping the pieces into the existing xml doc may not make sense" argument
18:41:59 dansmith yeah, I'm trying to come up with a concrete example that exists today, which may not be possible,
18:42:06 dansmith but surely may in the future
18:42:42 dansmith oh so,
18:42:53 dansmith <cputune> has a ton of stuff in it, not all numa-related right?
18:43:13 artom So, NUMA is sort of an abuse of language
18:43:31 artom CPU pinning isn't strictly NUMA
18:43:46 artom But that info is stored in our NUMA objects
18:43:53 dansmith cputune specifies the cache layout.. will the destination generate that too? can it? what if it differs from what the guest has now for some reason? the source will have to decide I would think
18:43:57 artom And it's one of the things we have to update
18:44:05 dansmith cache is?
18:44:11 dansmith or you mean pinning
18:44:24 artom Yeah pinning
18:44:29 dansmith yeah,
18:44:40 dansmith so I mean basically you're asking the destination for a lot of fragments
18:44:59 dansmith and just yanking those into the source document just strikes me as unsafe, or fragile
18:45:22 dansmith having generated my fair share of xml that I thought was valid, only to have to spend time with sax to figure out what I did that violated the schema...
18:45:45 artom Well, it'd be a matter of 'for numa-y element in source: if numa-y element in dest: replace the bits, dropping in the whole subtree if feasible'
18:46:33 dansmith really? what if the source generates fewer elements and you don't replace one of the source ones and now you have a layout that doesn't make sense? :)
18:46:47 artom So numatune I *think* would be fully replacable
18:46:52 dansmith aye
18:47:11 dansmith what if the source is older than the destination and the destination generates some layout, that doesn't make sense without an element you don't know about?
18:47:27 artom We encore nova service version, at least
18:47:32 dansmith like new libvirt adds cache affinity to numa node (just a fake example of course)
18:47:36 dansmith right, so that's my point,
18:47:46 dansmith instead of exposing feature flags and letting the source reason about it,
18:47:55 artom Well, libvirt doens't actually come into play here, just our driver
18:48:09 dansmith no, I know, but I'm saying we add support for some new thing
18:48:20 dansmith the destination needs to know and do a lot of compatibility handling
18:48:47 dansmith which it does anyway, but I just think if you open the gate that wide, it starts to have to care about the libvirt schema at a particular version, which by the way, service_version won't tell you :)
18:49:18 artom Yeah, sorry, the service version thing is just while we're on rocky/queens
18:49:41 dansmith right but there is a wide spectrum of libvirt, qemu and nova versions that may affect stuff like this
18:49:47 dansmith anyway, I have to run to lunch in a bit
18:49:56 dansmith but hopefully you've got some of my concerns in your head now
18:49:56 artom Once we move past that, it's completely conceivable for both source and dest to be > MIN_NUMA_LIVE_MIGRATION, and for the dest to generate some XML that the source doens't know about
18:50:24 dansmith sounds like you maybe need some spec text to generate this discussion and move to agreement yeah?
18:50:45 artom I suppose
18:51:00 dansmith no?
18:51:09 artom It wouldn't hurt
18:51:14 dansmith this strikes me as a thing you're going to want to have broad agreement on
18:51:25 artom I feel like having concrete code to strawman might be better
18:51:48 dansmith well, as long as you're okay with throwing it away, and make it clear it's for discussion then that's fine with me
18:52:30 artom Heh, well, maybe I'm not?
18:52:48 dansmith ...
18:53:03 dansmith well, just trying to help.. do whichever you think will be most successful :)
18:53:50 artom dansmith, right, sorry, didn't mean to come off as flippant
18:54:03 artom This discussion is definitely helpful and your time is appreciated :)
18:54:32 dansmith for me as well
18:54:47 dansmith now I have all my -1s lined up and it's not even noon :P
19:27:14 smcginnis I seem to recall hearing at one point that the version of libvirt-python used was dependent on the version of libvirt itself on the host. Can anyone confirm that?
20:14:19 openstackgerrit Merged openstack/nova stable/queens: [Stable Only] Add amd-ssbd and amd-no-ssb CPU flags https://review.openstack.org/576270
20:14:27 openstackgerrit Merged openstack/nova master: Fix bug to api-ref https://review.openstack.org/571375
20:24:49 openstackgerrit Dan Smith proposed openstack/nova stable/pike: [Stable Only] Add amd-ssbd and amd-no-ssb CPU flags https://review.openstack.org/577548
21:28:58 openstackgerrit Merged openstack/nova master: Fix nits from change Ia7cf4414feb335b3c2e863b4c8b4ff559b275c34 https://review.openstack.org/577314
21:41:16 openstackgerrit Merged openstack/nova master: libvirt: Log breadcrumb for known encryption bug https://review.openstack.org/577164
#openstack-nova - 2018-06-23
08:13:56 openstackgerrit jiang wei proposed openstack/nova master: Add action initiator attribute to the instance payload https://review.openstack.org/536243
14:10:37 openstackgerrit Merged openstack/nova master: Fix bug to filter_scheduler https://review.openstack.org/571998
#openstack-nova - 2018-06-24
01:52:57 openstackgerrit Zhenyu Zheng proposed openstack/nova master: Use ThreadPoolExecutor for max_concurrent_live_migrations https://review.openstack.org/563505
02:42:17 openstackgerrit Zhenyu Zheng proposed openstack/nova master: Use ThreadPoolExecutor for max_concurrent_live_migrations https://review.openstack.org/563505
16:44:30 openstackgerrit Lei Zhang proposed openstack/nova master: Add method to get cpu traits https://review.openstack.org/560317
#openstack-nova - 2018-06-25
02:20:16 openstackgerrit Yikun Jiang (Kero) proposed openstack/nova master: Change the anti-affinity Filter to adapt to new policy https://review.openstack.org/571166
02:20:17 openstackgerrit Yikun Jiang (Kero) proposed openstack/nova master: Adapt _validate_instance_group_policy to new policy model https://review.openstack.org/571465
02:20:18 openstackgerrit Yikun Jiang (Kero) proposed openstack/nova master: Microversion 2.64 - Use new format policy in server group https://review.openstack.org/567534
02:21:29 openstackgerrit Vu Cong Tuan proposed openstack/os-vif master: Add py36 testenv https://review.openstack.org/577686
02:59:53 openstackgerrit Merged openstack/nova stable/queens: Add policy rule to block image-backed servers with 0 root disk flavor https://review.openstack.org/563692
02:59:58 openstackgerrit Merged openstack/nova stable/pike: Fixed auto-convergence option name in doc https://review.openstack.org/576282
04:13:14 openstackgerrit Steve Kowalik proposed openstack/nova master: Switch to oslo_messaging.ConfFixture.transport_url https://review.openstack.org/573046
04:53:21 openstackgerrit Merged openstack/nova stable/pike: [Stable Only] Add amd-ssbd and amd-no-ssb CPU flags https://review.openstack.org/577548
05:11:35 openstackgerrit Hironori Shiina proposed openstack/nova master: Ironic: Check a last error of power action https://review.openstack.org/470754
05:55:34 openstackgerrit Deepak Mourya proposed openstack/nova master: Handle CannotDeleteParentResourceProvider to 409 Conflict https://review.openstack.org/577726
06:03:13 openstackgerrit Deepak Mourya proposed openstack/nova master: Handle CannotDeleteParentResourceProvider to 409 Conflict https://review.openstack.org/577726
06:12:32 gibi good morning nova
06:23:18 openstackgerrit Merged openstack/nova stable/pike: Change consecutive build failure limit to a weigher https://review.openstack.org/573248
07:12:58 openstackgerrit Chason Chan proposed openstack/nova master: [WIP] Fix the duplicated config options of api_database and placement_database https://review.openstack.org/577023
07:13:39 openstackgerrit Gergely Csatari proposed openstack/nova master: Adding oslo.service to doc requirements https://review.openstack.org/577095
07:29:46 openstackgerrit Deepak Mourya proposed openstack/nova master: Handle CannotDeleteParentResourceProvider to 409 Conflict https://review.openstack.org/577726
07:38:44 openstackgerrit Hironori Shiina proposed openstack/nova master: ironic: Proxy a few attributes of block device mapping https://review.openstack.org/554093
09:00:06 openstackgerrit Zhenyu Zheng proposed openstack/nova master: Compute: add support to abort queued live migration https://review.openstack.org/568542
09:11:31 openstackgerrit Lee Yarwood proposed openstack/nova stable/queens: libvirt: Log breadcrumb for known encryption bug https://review.openstack.org/577757
09:23:11 bauzas gibi: stephenfin: easy fix for reviews that'd help operators https://review.openstack.org/#/c/577424/
09:36:35 openstackgerrit Surya Seetharaman proposed openstack/nova master: Make nova list and migration-list ignore down cells https://review.openstack.org/575734
09:39:31 gibi bauzas: looking
10:41:36 openstackgerrit Chris Dent proposed openstack/nova master: Test alloc_cands with indirectly sharing RPs https://review.openstack.org/519601

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