| Posted | Nick | Remark | |
|---|---|---|---|
| #openstack-nova - 2020-07-24 | |||
| 16:14:11 | sean-k-mooney | luminous is the defualt in the devstack plugin ya | |
| 16:14:17 | dansmith | but CI is using nautilus | |
| 16:14:18 | sean-k-mooney | but ci i guess is overriding it | |
| 16:14:29 | dansmith | ceph version 14.2.2 (4f8fa0a0024755aae7d95567c63f11d6862d55be) nautilus (stable), process ceph-osd, pid 8952 | |
| 16:14:38 | sean-k-mooney | ya | |
| 16:14:44 | dansmith | can we set the backing store driver? | |
| 16:14:48 | dansmith | back to xfs? | |
| 16:15:07 | sean-k-mooney | we could but i think the better solution is to change how we do the mounting | |
| 16:15:14 | sean-k-mooney | bluestore is not the default | |
| 16:15:17 | sean-k-mooney | upstream | |
| 16:15:27 | sean-k-mooney | in ceph and downstream as of osp 16 | |
| 16:15:38 | sean-k-mooney | so its nice to test with bluestore | |
| 16:15:54 | dansmith | unless you see where we're setting it to bluestore, it would seem maybe the default changed in nautilus? | |
| 16:16:22 | sean-k-mooney | well after lumious in any case but yes i dont think we currently set it directly | |
| 16:16:54 | dansmith | you said "bluestore is not the default" above | |
| 16:17:03 | dansmith | so I'm confused about what you're proposing | |
| 16:17:42 | sean-k-mooney | oh i ment is | |
| 16:17:49 | sean-k-mooney | it is now the default in ceph | |
| 16:17:58 | sean-k-mooney | i filestore used to be the default before | |
| 16:18:14 | dansmith | okay that's what I was saying | |
| 16:18:36 | dansmith | I still don't get where the 10G comes from, other than that something is clearly different with blue vs xfs stores | |
| 16:18:46 | sean-k-mooney | bluestore has been the default for a few releases now. filestore is deprecated upstream and downstream in ops | |
| 16:19:06 | sean-k-mooney | dansmith: i think that is the default size that the ceph tool uses | |
| 16:19:19 | sean-k-mooney | when its creating a backing file | |
| 16:19:36 | dansmith | okay I don't see that anywhere | |
| 16:20:19 | sean-k-mooney | its being created by the ceph osd itself here https://zuul.opendev.org/t/openstack/build/13d8a055ff1b4be0b627205f4d51d50f/log/controller/logs/ceph/ceph-osd.0_log.txt#4 | |
| 16:20:26 | dansmith | I imagine that keeping the loopback mount for var lib ceph is ideal for the plugin as long as we have stable branches that use that | |
| 16:20:38 | dansmith | sean-k-mooney: yeah I get that :) | |
| 16:20:50 | dansmith | sean-k-mooney: I'm saying I don't know where 10G is set or assumed or whatever ;) | |
| 16:21:00 | sean-k-mooney | yes we can proably change that in the job? | |
| 16:21:07 | melwitt | dansmith: is it not here? https://zuul.opendev.org/t/openstack/build/13d8a055ff1b4be0b627205f4d51d50f/log/controller/logs/ceph/ceph-osd.0_log.txt#18 | |
| 16:21:24 | dansmith | lol | |
| 16:21:28 | dansmith | yes, I understand 10G is being used | |
| 16:21:34 | sean-k-mooney | or if the destack pluging is branched we can change it only on the branchs that use nautilus | |
| 16:21:35 | dansmith | I'm saying I don't see a config for that | |
| 16:21:54 | dansmith | https://docs.ceph.com/docs/mimic/rados/configuration/bluestore-config-ref/ | |
| 16:21:58 | sean-k-mooney | if there is a config it would be the ceph config file | |
| 16:22:03 | melwitt | oh, sorry, just saying that's a command that is setting 10G deliberately | |
| 16:22:28 | dansmith | melwitt: yep I think that's understood now | |
| 16:22:28 | melwitt | from what sean-k-mooney was saying, I thought no one saw a deliberate setting of it yet | |
| 16:22:41 | melwitt | that it was happening "automatically" | |
| 16:22:58 | melwitt | I am caught up now | |
| 16:23:16 | dansmith | all I'm saying is, I imagine that bluestore can have more than 10G of backing store, and if it's not basing that on actual disk free space, it's probably a config somewhere or something :) | |
| 16:23:51 | melwitt | yeah, I understand now | |
| 16:24:09 | melwitt | I misunderstood what sean was saying earlier | |
| 16:25:22 | dansmith | the bluestore config actually seems to be mostly focused on using physical devices | |
| 16:27:12 | sean-k-mooney | melwitt: it happens frequently that people missunderstad me. well not that often if i type what i ment to type but i am bad at not doing that | |
| 16:28:56 | melwitt | sean-k-mooney: eh, I often have trouble understanding people so by our powers combined... ! | |
| 16:30:46 | dansmith | I HAVE NO IDEA WHAT YOU PEOPLE ARE SAYING | |
| 16:31:09 | melwitt | I AM GOOD AT DEALING WITH PEOPLE | |
| 16:31:47 | sean-k-mooney | stephenfin: talking about storage does this to people | |
| 16:32:16 | sean-k-mooney | just taking a step back | |
| 16:32:30 | sean-k-mooney | we are happy we know where the 10G size is comming from now | |
| 16:32:36 | melwitt | StOrAGE | |
| 16:33:10 | sean-k-mooney | and that we are proably just hitting a real no valid host error because we are actully providing 10G to cpeh instead of 24 | |
| 16:33:28 | sean-k-mooney | so the ceph jobs failrues are not related to dansmith's recent changes to the job | |
| 16:33:35 | sean-k-mooney | yes? | |
| 16:34:10 | dansmith | sean-k-mooney: yeah I thought we were assuming that | |
| 16:34:16 | dansmith | because it's clearly just placement | |
| 16:34:31 | dansmith | my job might be slower (or faster) causing us to hit it more than we were or something | |
| 16:35:05 | sean-k-mooney | so we just either a.) swap back to file store to get the old behavior or b.) mount our loopback file in such a way that the bluestore block device uses our 24G loopback device instead of creating its own | |
| 16:35:29 | dansmith | yeah so I figured going back to xfs would be ideal for compatibility with everything | |
| 16:35:38 | dansmith | my system clearly gets xfs | |
| 16:35:51 | dansmith | I assume the workers are getting blue because they're newer ubuntu or something | |
| 16:36:00 | dansmith | I'm still on bionic | |
| 16:36:01 | sean-k-mooney | dansmith: sure but eventurally we will have to move since i think filestore is deprected in ceph | |
| 16:36:05 | dansmith | sure | |
| 16:36:16 | dansmith | pain now or pain later | |
| 16:36:21 | dansmith | pain later might be someone else's pain :P | |
| 16:36:52 | sean-k-mooney | so i guess what we are looking for is a ceph config option to select filestore for the osd backend | |
| 16:37:43 | sean-k-mooney | that or we set it on the osd create command | |
| 16:38:02 | dansmith | yeah | |
| 16:38:37 | sean-k-mooney | so this code https://github.com/openstack/devstack-plugin-ceph/blob/master/devstack/lib/ceph#L475-L484 | |
| 16:39:03 | sean-k-mooney | that inital sudo ceph -c ${CEPH_CONF_FILE} osd create | |
| 16:39:06 | dansmith | well, the other option is to figure out how to make blue use 20ish G instead of 10, | |
| 16:39:20 | dansmith | which would be less impactful than retooling the mount stuff in the ceph plugin | |
| 16:40:00 | sean-k-mooney | well we are mounting it on /var/lib/ceph | |
| 16:40:08 | sean-k-mooney | so i guess this is already plugin specific | |
| 16:40:24 | sean-k-mooney | we are likely resuing the same function that is used for cinder and just passing the mount path | |
| 16:40:57 | sean-k-mooney | ya we are just calling create_disk https://github.com/openstack/devstack-plugin-ceph/blob/master/devstack/lib/ceph#L387 | |
| 16:41:01 | dansmith | cinder just wants a loop not a mounted fs though right/ | |
| 16:41:52 | sean-k-mooney | maybe this is the fucntion in devstack https://github.com/openstack/devstack/blob/eee60c76719c02c08dba7b7fb703798a056b22b9/functions#L758-L789 | |
| 16:42:19 | sean-k-mooney | that kind of looks like a hack | |
| 16:42:41 | sean-k-mooney | e.g. that does not look like it was created orginally for ceph | |
| 16:43:26 | melwitt | hm, I found this https://forum.proxmox.com/threads/proxmox-ceph-osd-partition-created-with-only-10gb.55291/ | |
| 16:43:31 | sean-k-mooney | oh its for swift orginially | |
| 16:46:20 | sean-k-mooney | i think the "sudo ceph-osd -c ${CEPH_CONF_FILE} -i ${OSD_ID} --mkfs" is the one we would need to modify | |
| 16:49:32 | sean-k-mooney | melwitt: that does seam like the same issue more or less | |
| 16:49:48 | melwitt | yeah, I'm having trouble understanding it | |
| 16:50:50 | melwitt | the last comment links to another post https://forum.proxmox.com/threads/where-can-i-tune-journal-size-of-ceph-bluestore.44000/ where they're talking about tuning journal size and bluestore_block_db_size and bluestore_block_wal_size | |
| 16:51:02 | melwitt | and I don't know what any of that is or means | |
| 16:51:22 | melwitt | (in ceph.conf) | |
| 17:01:31 | sean-k-mooney | those are not realated to the data storage size of the osd | |
| 17:01:55 | sean-k-mooney | blustore has an embeed database that track where the logic block are located on disk | |
| 17:02:27 | sean-k-mooney | wal i think it the write ahead log or somethingl like that | |
| 17:02:39 | sean-k-mooney | its part of how it does write journalling | |
| 17:03:02 | sean-k-mooney | in both cases they are turning parmatner for how bluestore can save its metadata | |
| 17:03:56 | sean-k-mooney | unlike file sotre it can save it inline in the blockdevice it is managening or it can save it oh external devices and they support tuneing of the sizing of them independelty | |
| 17:04:33 | openstackgerrit | Artom Lifshitz proposed openstack/nova master: Handle Neutron errors in _post_live_migration() https://review.opendev.org/729763 | |
| 17:09:57 | melwitt | sean-k-mooney: found a new thing https://bugzilla.redhat.com/show_bug.cgi?id=1597048 | |