| Posted | Nick | Remark | |
|---|---|---|---|
| #openstack-nova - 2017-12-18 | |||
| 20:51:04 | mriedem | we have 12 candidate hosts, | |
| 20:51:15 | mriedem | initial select_destinations call for this create request | |
| 20:51:25 | mriedem | and we log "Re-scheduling is disabled" 12 times, once per host, because of the RetryFilter, | |
| 20:51:43 | mriedem | and i think it's all because we don't populate the 'retry' field in the RequestSpec before calling select_destinations the first time | |
| 20:52:04 | mriedem | during create we call the scheduler here http://git.openstack.org/cgit/openstack/nova/tree/nova/conductor/manager.py#n1016 | |
| 20:52:15 | mriedem | and we don't populate retry until http://git.openstack.org/cgit/openstack/nova/tree/nova/conductor/manager.py#n1108 | |
| 20:52:23 | mriedem | i'm not sure if that was ever by design | |
| 20:52:49 | mriedem | looking at the old build_instances method, we'd populate retry before calling the scheduler http://git.openstack.org/cgit/openstack/nova/tree/nova/conductor/manager.py#n543 | |
| 20:53:19 | mriedem | again, probably not our issue here since max_attempts=3 by default, and i verified that in this job, but it sure is confusing in the logs | |
| 20:57:52 | mriedem | https://bugs.launchpad.net/nova/+bug/1738876 | |
| 20:57:52 | openstack | Launchpad bug 1738876 in OpenStack Compute (nova) "Scheduler logs "Re-scheduling is disabled" on initial server create scheduling even though max_attempts>0" [Medium,Triaged] | |
| 21:09:32 | edleafe | mriedem: with alternates, isn't the RetryFilter supposed to go away? | |
| 21:09:58 | mriedem | i suppose it would over time | |
| 21:10:07 | edleafe | since you won't try the same host more than once? | |
| 21:10:32 | edleafe | IOW, it'll always be a noop | |
| 21:17:18 | mriedem | edleafe: this shows that we're getting duplicate alternates http://logs.openstack.org/89/527289/1/check/ironic-tempest-dsvm-ipa-wholedisk-agent_ipmitool-tinyipa-multinode/22826a2/logs/screen-n-super-cond.txt.gz#_Dec_15_23_17_04_949754 | |
| 21:17:29 | mriedem | Selected host: ubuntu-xenial-inap-mtl01-0001472200; Alternates: [u'ubuntu-xenial-inap-mtl01-0001472200', u'ubuntu-xenial-inap-mtl01-0001472200'] | |
| 21:19:12 | mriedem | hmm | |
| 21:19:13 | mriedem | https://github.com/openstack/nova/blob/master/nova/scheduler/filter_scheduler.py#L361 | |
| 21:19:17 | mriedem | host not in selected_hosts | |
| 21:19:30 | mriedem | we don't have a HostState.__eq__ override | |
| 21:20:02 | edleafe | mriedem: wait - a HostState object isn't equal to itself? | |
| 21:21:42 | openstackgerrit | Merged openstack/nova stable/pike: Make request_spec.spec MediumText https://review.openstack.org/528330 | |
| 21:22:26 | mriedem | edleafe: i'm not sure if that is the issue, | |
| 21:22:43 | mriedem | but https://github.com/openstack/nova/blob/master/nova/scheduler/filter_scheduler.py#L361 is the place where we'd filter out duplicate alternates wouldn't it? | |
| 21:23:07 | mriedem | oh wait, no | |
| 21:23:57 | mriedem | maybe the logging you added to conductor is just incomplete because it doesn't also log the nodename? | |
| 21:24:33 | edleafe | that could be the case | |
| 21:24:54 | edleafe | I have some unit tests that verify that there aren't dupes added to alternates | |
| 21:25:55 | mriedem | ok, so in the case of ironic, we could be getting alternate nodes properly from the scheduler | |
| 21:26:07 | edleafe | I can add nodename and push a revision if you want to test that theory | |
| 21:26:08 | mriedem | but the reschedule logic doesn't take that into account | |
| 21:26:24 | mriedem | edleafe: yeah let's do that - i left some other comments in conductor manager about that log message | |
| 21:28:22 | edleafe | ok | |
| 21:28:54 | mriedem | this also explains why http://logs.openstack.org/89/527289/1/check/ironic-tempest-dsvm-ipa-wholedisk-agent_ipmitool-tinyipa-multinode/22826a2/ passed the 2nd time i checked it, | |
| 21:29:09 | mriedem | it's just totally random if we pick one of the alternates which is a different node on a different hose when we reschedule | |
| 21:29:36 | mriedem | jroll: so to answer your question, reschedules with alternate ironic nodes might work, but it's not designed to work yet :) | |
| 21:29:46 | jroll | heh, cool | |
| 21:30:47 | openstackgerrit | Ed Leafe proposed openstack/nova master: Make conductor pass and use host_lists https://review.openstack.org/511358 | |
| 21:31:36 | edleafe | mriedem: ^^ now with improved logging! | |
| 21:32:11 | openstackgerrit | Jay Pipes proposed openstack/nova master: WIP - Support aggregate affinity filters https://review.openstack.org/528804 | |
| 21:35:12 | mriedem | edleafe: you changed one thing, broke one thing, and missed some other things :) | |
| 21:35:37 | edleafe | about par for the course | |
| 21:35:42 | mriedem | before you change, hold up | |
| 21:36:57 | mriedem | so actually, this should work for ironic | |
| 21:37:27 | mriedem | there is nothing in the scheduler or conductor retry loop code, that i can see, which is filtering alternates based on just the host | |
| 21:38:12 | mriedem | so the failure we hit in the ironic job originally where it tried to upcall, is probably just do to not handling the final retry properly and killing it | |
| 21:38:21 | mriedem | is_retry = host_lists is not None | |
| 21:38:30 | mriedem | on the last reschedule, that could be None or an empty list yeah? | |
| 21:39:05 | edleafe | how could it be None? | |
| 21:40:20 | mriedem | # 'host_lists' will be None in one of two cases: when running | |
| 21:40:20 | mriedem | # cellsv1, or during a reschedule from a pre-Queens compute. | |
| 21:40:49 | edleafe | yeah | |
| 21:40:50 | mriedem | i think i explain the problem scenario here https://review.openstack.org/#/c/511358/41/nova/conductor/manager.py@599 | |
| 21:41:00 | edleafe | not on a reschedule | |
| 21:41:03 | mriedem | we have 2 alternates, and let's say we're on the last one | |
| 21:41:10 | mriedem | we pop that last entry from the host_list | |
| 21:41:22 | mriedem | pass it to compute, which fails, and reschedules, and passes that empty list back to build_instances | |
| 21:41:52 | edleafe | yup | |
| 21:41:57 | edleafe | it won't be None | |
| 21:42:11 | mriedem | i think i'm confusing myself | |
| 21:43:02 | edleafe | it will be empty if there are no more alternates | |
| 21:43:06 | edleafe | but it will be a list | |
| 21:44:50 | edleafe | mriedem: https://review.openstack.org/#/c/511358/41/nova/compute/manager.py@1905 | |
| 21:45:18 | mriedem | yeah the list of lists there really confuses me | |
| 21:45:23 | mriedem | you said you're doing that because of [instance] | |
| 21:45:30 | mriedem | but i don't think we need to follow that pattern here | |
| 21:46:17 | edleafe | conductor gets [instance], so it need [host_list] | |
| 21:46:27 | edleafe | compute gets instance, so it needs host_list | |
| 21:46:28 | mriedem | so the zip works? | |
| 21:46:52 | edleafe | that's one of many reasons | |
| 21:47:03 | edleafe | it needs a host_list for each instance | |
| 21:47:43 | mriedem | ok, not a major issue for me atm | |
| 21:47:53 | mriedem | for that one ci job failure, this is the reason the first selected node failed | |
| 21:47:54 | mriedem | http://logs.openstack.org/89/527289/1/check/ironic-tempest-dsvm-ipa-wholedisk-agent_ipmitool-tinyipa-multinode/406d4ab/logs/screen-n-cpu.txt.gz#_Dec_12_22_23_48_399346 | |
| 21:47:58 | mriedem | ComputeHostNotFound: Compute host 5 could not be found. | |
| 21:49:05 | edleafe | any idea why that host couldn't be found? | |
| 21:49:22 | mriedem | nope | |
| 21:49:34 | mriedem | we might not be using the proper cell context | |
| 21:52:02 | mriedem | so we hit the first selected node, which fails because of compute node not found, | |
| 21:52:09 | mriedem | and we cast up to the cell conductor to reschedule and hit this http://logs.openstack.org/89/527289/1/check/ironic-tempest-dsvm-ipa-wholedisk-agent_ipmitool-tinyipa-multinode/406d4ab/logs/screen-n-cond-cell1.txt.gz#_Dec_12_22_23_48_751837 | |
| 21:55:30 | mriedem | AHA | |
| 21:55:38 | mriedem | i see the problemo | |
| 21:55:39 | mriedem | oh ed | |
| 21:55:43 | mriedem | ed ed ed | |
| 21:56:24 | edleafe | you were getting me confused. How could the compute call back when the compute wasn't found? | |
| 21:58:52 | mriedem | comments line | |
| 21:58:53 | mriedem | *inline | |
| 21:59:01 | mriedem | you were passing host_list using the wrong arg | |
| 21:59:04 | edleafe | looking | |
| 21:59:10 | mriedem | that's why it was None when it came back up and we tried to hit the scheduler again | |
| 21:59:27 | mriedem | use kwargs ftw | |
| 22:00:10 | mriedem | so i think ironic reschedules should be totally fine | |
| 22:00:11 | mriedem | jroll: ^ | |
| 22:00:36 | mriedem | code as is is busted so it wasn't trying alternates | |
| 22:00:42 | mriedem | once we fix that, things should be good | |
| 22:01:33 | jroll | nice | |
| 22:04:25 | openstackgerrit | Ed Leafe proposed openstack/nova master: Make conductor pass and use host_lists https://review.openstack.org/511358 | |
| 22:06:40 | edleafe | mriedem: ^^ updated | |
| 22:07:28 | mriedem | edleafe: ok, that should fix the actual reschedule issue, but still missing comments from PS41 so re-applied my -1 | |