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#openstack-nova - 2017-03-29
19:26:33 bauzas agreed
19:26:52 edleafe oomichi: just proposed a fix: https://review.openstack.org/451536
19:26:52 mriedem i think the goal is get as much prep work done in pike, and then cutover early in queens and drop the caching scheduler
19:27:15 bauzas mriedem: yup, hence why I provided this spec
19:27:41 bauzas mriedem: I prefered to leave us discussing about the possibilites before I could implement that by Queens
19:27:59 bauzas mriedem: also, unrelated, I saw https://review.openstack.org/#/c/389216/
19:28:16 bauzas mriedem: I do wonder if we should be discussing about reservations with the Blazar team
19:28:50 bauzas for the moment, Blazar is using aggregates for reserving computes, but I'd prefer they could discuss with us about using the placement API too
19:29:11 bauzas mriedem: FWIW, I was a Blazar core 3 years ago
19:31:59 mriedem isn't blazar dead?
19:32:59 bauzas mriedem: not really
19:33:08 bauzas mriedem: it resurrected 6 months ago
19:33:21 bauzas mriedem: because of something having 3 letters :p
19:33:45 bauzas Nouvelle Formule Verifiée
19:33:56 jaypipes Neverending Feature Velocity.
19:34:31 jaypipes mriedem: Blazar is now in OPNFV.
19:34:59 bauzas not really, but yeah
19:35:24 bauzas OPNFV folks looked at some reservation possibilities, and they saw Blazar
19:36:12 bauzas honestly, I'm good with the APIs, but I think we could be somehow use placement for their backends
19:36:35 bauzas it's about saying "I want this compute in 3 hours for 2 mins"
19:38:03 bauzas jaypipes: do you agree with me possibly asking Blazar and those folks https://review.openstack.org/#/c/389216/ discussing about how to create reservations using placement as a backend for Blazar?
19:38:31 bauzas jaypipes: tbc, I don't think placement should think about leases or other time stuff
19:38:52 bauzas jaypipes: I just think they could be creating allocations using specific RPs
19:39:02 mriedem rub some placement on it
19:39:04 mriedem problem solved
19:39:27 jaypipes bauzas: placement wouldn't even be involved until the claim was actually made, though...
19:39:36 bauzas jaypipes: I know
19:39:50 bauzas the discussion wouldn't be for something Pike and I doubt Queens
19:40:15 bauzas but having folks around discussing about reservations would also help folks like https://review.openstack.org/#/c/389216/
19:40:33 bauzas because lots of operators use server groups for that
19:40:51 bauzas and we know how the server group API can be difficult to be used :)
19:41:12 jaypipes bauzas: I need to read that spec. sorry, haven't had a chance yet :(
19:41:35 bauzas jaypipes: tl,dr: it's about saying "I want to reserve this space into the servergroup"
19:43:02 jaypipes bauzas: how does AWS/EC2 approach a use case like that? Can I tell EC2 "hey, can you please just reserve a rack of machines for me to be guaranteed access and use of some time in the future and don't charge me for anything. kthxbai"
19:44:22 bauzas jaypipes: well, AWS doesn't propose that, they rather propose an invoice API called 'spot-instances' and 'reserved computes' :p
19:44:46 bauzas I'm betting that invoice API translates into something real about capacity management tho
19:45:43 jaypipes bauzas: spot instances are totally different. those are instances that can be slotted into "available" resource nodes but terminated if a higher priority workload needs the space.
19:46:02 bauzas jaypipes: correct
19:46:12 bauzas jaypipes: but that's an invoice SLA
19:46:45 jaypipes bauzas: lemme finish the traits reviews and then I'll read that spec.
19:46:53 bauzas jaypipes: heh, no rush at all
19:47:35 bauzas I was just considering the interest of proposing a Forum session about that, that's it
19:47:55 bauzas given the deadline (Apr 2nd)
19:48:13 bauzas either way, it's a priority for my duty work :)
19:48:24 bauzas I just take that as a personal interest in it
19:48:37 bauzas it's *not* a priority, dang.
20:04:12 openstackgerrit Sujitha proposed openstack/nova master: Adding auto_disk_config field to InstancePayload https://review.openstack.org/419185
20:04:58 openstackgerrit Sujitha proposed openstack/nova master: Reduce calls to load_tags() to 0 https://review.openstack.org/435146
20:12:44 jaypipes bauzas: -2 on that affinity group spec. see my review...
20:14:23 bauzas jaypipes: well, there are usecases where people want to define a lease, and start paying for that lease when it starts
20:14:46 bauzas here, booting instances in advance is suboptimal for an OPEX PoV
20:14:57 dansmith why?
20:14:57 jaypipes bauzas: see my review. there's no difference between reserving and using a resource in Nova.
20:15:10 dansmith boot it now, rebuild it if you need a different image later
20:15:12 bauzas jaypipes: in Nova, I totally agree
20:15:20 bauzas lemme make it cleat
20:15:23 bauzas clear
20:15:30 bauzas I'm not talking at all about Nova providing that
20:15:47 bauzas and I'm -2 on that idea too if you prefer
20:15:47 jaypipes bauzas: the inability of another tenant using that "slot" of resources makes the reservation exactly equal in cost to the use of something.
20:16:42 openstackgerrit Anusha Unnam proposed openstack/nova master: Add description to policies in servers_migrations.py https://review.openstack.org/451487
20:16:56 bauzas jaypipes: I'm trying to explain that without a whiteboard, hold on
20:17:26 bauzas jaypipes: there are situations where, as a tenant, I want to make sure I will have the capacity in 2 hours
20:17:37 bauzas for a certain duration
20:17:43 bauzas unrelated to my quotas
20:18:40 bauzas jaypipes: the fact that another tenant could use all the resources *before* or *after* my period doesn't really hurt me
20:19:18 mriedem jaypipes: thanks for looking at https://review.openstack.org/#/c/441692/ again
20:20:07 bauzas jaypipes: what people want is some way to say "I'm gonna lock some resources not for now, but when my period will start"
20:20:40 bauzas dansmith: rebuild doesn't guarantee you it will success by the time you do it
20:20:54 dansmith bauzas: eh?
20:20:57 mriedem neither does reserving and saying you're going to create a server in 2 hours
20:21:12 mriedem if ceph crashes
20:21:20 bauzas dansmith: you're asking the scheduler for rebuild
20:21:56 mriedem maybe this is the thing where people have asked in the past for a way to create a server in stopped state immediately
20:22:01 mriedem as a workaround for a lack of reservations
20:22:05 bauzas mriedem: agreed, all of that supposes a fully functional cloud
20:22:23 bauzas mriedem: yup, shelved instances was the hack
20:22:35 bauzas shelved *offloaded*
20:22:41 mriedem rather than just create and then stop in separate calls
20:22:58 bauzas but by the time the instance unshelves, you have no guarantee that it will succeed
20:23:15 dansmith bauzas: rebuild doesn't ask anything of the scheduler right?
20:23:32 bauzas dansmith: lemme verify, my guts say the contrary
20:23:51 dansmith only for evacuate, IIRC
20:24:25 mriedem the scheduler has to take into account image properties in the new image
20:24:26 mriedem for rebuild
20:24:50 mriedem i think we actually have a bug for that,
20:24:54 mriedem because we don't do that today
20:25:08 dansmith bauzas: host=instance.hosdt
20:25:34 mriedem that's the bug
20:25:49 mriedem the new image could have properties that don't fit the instance's existing host
20:25:57 bauzas dansmith: yeah you're right, just verified
20:26:06 bauzas dansmith: and I think it's a miss
20:26:06 dansmith mriedem: right, but rebuild is supposed to be in place
20:26:23 openstack Launchpad bug 1667667 in OpenStack Compute (nova) "Rebuilding instance ignores image's property hw_disk_bus" [Low,Confirmed]
20:26:23 mriedem https://bugs.launchpad.net/nova/+bug/1667667
20:26:25 bauzas mriedem: resize != rebuild
20:26:31 mriedem bauzas: i know
20:26:46 bauzas mriedem: yeah I know you know, but it's not taking a new flavor, right?
20:26:55 bauzas oh, the image props
20:26:59 dansmith image

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