15:02:05 #startmeeting fog-edge-massively-distributed-clouds 15:02:07 Meeting started Wed Jun 21 15:02:05 2017 UTC and is due to finish in 60 minutes. The chair is msimonin. Information about MeetBot at http://wiki.debian.org/MeetBot. 15:02:08 Useful Commands: #action #agreed #help #info #idea #link #topic #startvote. 15:02:10 The meeting name has been set to 'fog_edge_massively_distributed_clouds' 15:02:23 #chair parnexius 15:02:24 Current chairs: msimonin parnexius 15:02:44 #topic roll call 15:02:48 Hello everyone 15:02:50 hi..o/ 15:02:50 Hello folks ! 15:03:07 Let's see who's around :) 15:03:08 o/ 15:03:10 o/ 15:03:16 o/ 15:03:16 o/ 15:03:45 o/ 15:04:12 Adrien has posted an Agenda for the meeting but will not be joining us. Mat and I will chair today 15:04:27 #link https://etherpad.openstack.org/p/massively_distributed_ircmeetings_2017 15:04:50 today we are at line 810 15:05:10 o/ 15:05:20 Feel free to add your name 15:05:44 It Seems we can start 15:05:57 #topic announcements 15:06:19 As parnexius said _ad_rien_ is not available today 15:06:37 so I'll try to transmit his announcements :) 15:07:07 First thing is that we are in touch wit ESTI MEC 15:07:13 #link http://www.etsi.org/technologies-clusters/technologies/multi-access-edge-computing 15:07:39 They have some architecture work done there 15:08:09 and we are now currently discussing with them to see if OpenStack can be used in their architecture 15:08:20 at least identify some building blocks 15:09:05 Great idea. I have started using some of their material in the use case development. 15:09:10 More on that later. 15:09:15 cool ! 15:10:11 I think we can move to the next topic 15:10:29 #topic AMQP alternatives 15:10:49 kgiusti ansmith any updates ? 15:10:49 hey! 15:11:05 kolla work is progressing nicely 15:11:31 andy and I have started an epad to define tests of the messaging bus 15:11:41 link in epad 15:12:07 mostly focused on messaging testing 15:12:07 thanks for this proposal kgiusti 15:12:13 at this point. 15:12:36 cloud level messaging test tools explored a bit 15:13:10 but really need help with defining the openstack cloud deployment arch to help define the best messaging topology to tests 15:13:34 err - "most appropriate messaging topology" for the cloud deployment 15:14:06 by topology: you mean where to put the router and what links between them ? 15:14:15 so please weigh in if you have any suggestions for messaging-oriented tests, failure scenarios, etc. 15:14:32 msimonin: yeah - the optimal distribution of routers "under" the cloud 15:14:43 kgiusti: which link is that in the epad (the one on strawman proposal) 15:15:00 parnexius: line 834 15:15:50 kgiusti: by router, you mean message router (like rabbitmq instances). 15:16:09 kgiusti: I guess, we should test several topologies 15:16:26 parnexius: in general yes, but that really depends on the tech used (rabbitmq/zeromq/router) 15:16:45 I mean, putting router on all physical nodes vs router on one leader node 15:16:46 for example: rabbitmq would be limited to clustering for scale 15:17:03 kgiusti: so if I understand the point right a router topology would include whether the router is deployed in the edge node, or only in a central location. 15:17:04 rcherrueau: that's one scenario for the router, yes 15:17:23 parnexius: yes - the router model is the most flexible, 15:17:27 meshing is also important I guess. Going with a full mesh between rooters is not the same thing than going with a star mesh 15:17:42 and thus most complex - we need to consider redundancy, locality of traffic, etc 15:18:13 rcherrueau: right - for example, how many network or router failures should be tolerated? 15:18:53 Is Dynamic routing available in these solutions? 15:19:02 I don't know, I much as OpenStack tolerate no :) 15:19:18 as much as* 15:19:44 So High-Availability would need to be provided by the solution (RabbitMQ, ZeroMQ, ....) 15:19:46 parnexius: yes - all routing is dynamic 15:20:15 kgiusti: can you please elaborate? 15:20:49 What would happen if a router on a node becomes unreachable? 15:20:58 parnexius: sure - regarding dynamic routing I'm assuming you mean re-routing around network failures 15:21:27 parnexius: if the clients have a fail-over router configured, that will be tried in recovery. 15:21:55 OK! I would call that static. but you are right it is a little dynamic. 15:22:20 parnexius: if there are redundant routers on the node (hot standby) that would take over (assuming redundant network paths) 15:23:17 parnexius: topology is one factor, the other is over-provisioning for throughput 15:23:45 parnexius: eg, if we lose a rabbit in a cluster, how does that reduce overall capacity? 15:23:58 I think we need time to get through what is written on the epad 15:24:13 msimonin: yep 15:24:16 and give you feedback 15:24:26 msimonin: and questions! :) 15:24:51 #info kgiusti share a premilinary "message plane load testing" 15:24:58 #link https://etherpad.openstack.org/p/1BGhFHDIoi 15:25:07 (just recording some stuffs :) ) 15:25:25 Can we iterate on the mailing list ? 15:25:45 and/or direclty on the document until next meeting 15:25:47 msimonin: yes - I did send an email just before the meeting regarding this 15:26:04 msimonin: Good Point. We shoudl all take action to be more active outside of IRC sessions. 15:26:07 msimonin: so folks not present can get the epad 15:27:11 kgiusti ansmith anything else on qpid dispatch router ? 15:27:17 fyi: http://lists.openstack.org/pipermail/openstack-dev/2017-June/118716.html 15:27:29 I'm good - andy? 15:27:33 good 15:28:58 Should we move to next topic then 15:29:13 right parnexius :) 15:29:20 *was reading the ml :) * 15:29:23 so 15:29:26 next topic 15:29:32 #topic cockroachdb 15:30:00 So I would say that similarly to the work on the messaging layer 15:30:41 there has been a mail on the ml about using cockroadb as an alternative backend for keystone 15:31:13 CockroachDB could be very interesting also in the context of a massively distributed cloud 15:32:00 Would that mean the database is replicated to all edge nodes? 15:32:03 cool will have to read through those notes 15:32:26 we had a meeting with some cockroachdb folks last week 15:32:30 a very first contact 15:33:07 parnexius: the same as qpid the topology will need to be defined 15:33:14 parnexius: not necessarily. With cockroachdb, you can tell which tuples should be replicated and which should not. 15:34:13 So 15:34:31 But this is not an opensource solution! 15:34:42 no, this is 15:35:13 Spanner is proprietary, CockroachDB is opensource 15:35:22 * rcherrueau check the licence 15:35:25 OK. I see it now. 15:35:44 So at Inria we are very much interesting in evaluating this 15:36:06 but we'll need support ! 15:36:59 parnexius: Apache License, Version 2.0, for community 15:37:30 Changing the DB backend here we'll require to resurect the postgresql driver, choose a service (keystone, nova, glance …) to make primary evaluation 15:37:32 and so on 15:37:52 Ceilometer ? 15:38:18 parnexius: yes it could be as well 15:38:35 so there's a lot of exciting stuff to do 15:38:38 so my question is 15:38:52 how to make people as excited as I am about this ? 15:39:36 that's a good question, there will be a fair amount of pushback on using cockroachdb 15:39:46 msimonin: why are you excited? 15:40:02 mostly I think around who will actually do the work in terms of the openstack testing system 15:40:37 parnexius: to speak roughly cockroach is noSQL with ACID properties 15:41:32 and Why is ACID important to our usecases? would performance be more important? 15:42:38 I would imagine a lot of code would have to be rewritten if the db were not ACID 15:43:21 I should add that cockroach is compatible with sqlalchemy 15:43:28 parnexius: ACID or not, Cockroach speaks Postgres protocol. That means -- in principle -- using it would be as simple as configuring oslo.db to connect to Cockroach 15:44:57 parnexius: The thing is, you have to implement ACID properties to implement pgsql protocol 15:45:43 To conclude here 15:45:49 Great discussion: some requirements are popping up here. 15:46:28 parnexius: yes ? 15:46:35 Performance, ACID, noSQL, pgsql 15:47:21 we need to get our heads together and define what is important to massively distributed. 15:47:56 right parnexius 15:48:16 please conclude. 15:48:55 parnexius: It would be cool is someone can look at Keystone db API/db requests and says which parts require string consistency (ACID) 15:49:08 strong consistency* 15:49:26 I'll take an action on this 15:49:32 I'll ping keystone guys 15:49:53 #action msimonin get in touch with keystone about cockroach 15:49:58 you should look at Nova too. 15:50:18 If none require strong consistency, then we can go with NoSQL -- but this means, we have to rewrite the db part of Keystone 15:50:22 keystone db tends to be centralized... while nova can be distributed. 15:50:27 the step after will be nova 15:50:49 the initial idea was from keystone 15:50:59 My point is we should focus on the aspects that are more relevant to Massively distributed. 15:51:02 how can nova be distributed? you mean cells? 15:51:37 #topic use-case definitions/dicussions 15:51:37 I mean that nova has components in each cells or edge nodes..... While keystone is usually central to a region ar the master cell. 15:51:54 Great transition. 15:52:08 parnexius: serverascode: let's see what keystone guy had in mind when proposing cockroach 15:52:28 About Use cases. 15:52:34 yes go on :) 15:52:37 parnexius: In multi-region scenarios, some also put keystone in each region and make it consistent using galera 15:52:59 I have uploaded some slides on goold doc. They touch on this very topic. 15:53:33 very bad experience with galera cluster. MySQL nbd better experience but requiere very services and complicated. 15:53:51 #link https://docs.google.com/presentation/d/1sBczuC2Wu1d_misBmPahLPdvyhOI4QuVy129EHunuUM/edit?usp=sharing 15:54:13 I will follow kgiusi example and send in an email. 15:54:16 many people have run galera sucessfully, and that is where some pushback will come from 15:54:28 Nil_: I have no doubt on that :) 15:54:31 parnexius: +1 for the ml 15:54:49 but the most I've seen anyone mention is 12 regions with a shared galera over all of them 15:55:13 where was hopefully with something like cockroachdb we could do many more regions 15:55:14 I was hoping that I could get some input from the team. and the discussion on galera and coackroach is relevant. 15:55:37 too many interesting topics here :) 15:55:51 Let's move this discussion to the mailing list. 15:55:55 maybe CockroachDB, i read gitup and very interesting... 15:55:57 serverascode: Galera is not an option in our usecases because of the WAN latency 15:56:18 parnexius: ok 15:56:35 I'm just letting you know the pushback we will get :) 15:56:44 is everyone interested in this discussion, or should we create a subteam. 15:57:17 actually I think we should move this discussion in the beginning next time :) 15:57:29 Msimonin: please give me action to take discussion to ML and let's move to close the meeting. 15:57:33 sure 15:57:56 #action parnexius starts a thread on the ml about massively distributed use cases 15:58:09 We have 2 min left :( 15:58:17 #topic open discussion 15:58:30 just leaving a question for next session, is discussion about how implement distributed UCs in terms of networking ? 15:58:46 UCs ? 15:58:48 ml2/3, tricircle, etc ? 15:58:55 just a quick intro.. from LCOO 15:58:57 UC = Use cases. 15:59:01 kk :) 15:59:02 Hi, I’m Sampath from NTT, one of the persons driving Ext ream testing (Destructive Testing) in LCOO with jamemcc 15:59:33 sorry guys 15:59:34 =) 15:59:50 let's try to iterate as much as possible between meetings 15:59:56 on the ml for example 15:59:57 +! 15:59:59 +1 16:00:01 #endmeeting