Alexey, I kindly ask you to move the meeting a little bit earlier, ideal variant -- in the morning.
ср, 25 нояб. 2020 г. в 20:10, Alexey Goncharuk <alexey.goncha...@gmail.com>: > Folks, let's have the call on Friday, Nov 27th at 18:00 MSK? We can use the > following waiting room link: > https://zoom.us/j/99450012496?pwd=RWZmOGhCNWlRK0ZpamdOOTZsYTJ0dz09 > > Let me know if this time works for everybody. > > ср, 25 нояб. 2020 г. в 16:42, Alexey Goncharuk <alexey.goncha...@gmail.com > >: > > > Folks, > > > > I've made some edits in IEP-61 [1] regarding the group membership service > > and transaction protocol interaction with the replication infrastructure, > > please take a look before our Friday call. > > > > [1] > > > https://cwiki.apache.org/confluence/display/IGNITE/IEP-61%3A+Common+Replication+Infrastructure > > > > пн, 23 нояб. 2020 г. в 13:28, Alexey Goncharuk < > alexey.goncha...@gmail.com > > >: > > > >> Thanks, Ivan, > >> > >> Another protocol for group membership worth checking out is RAPID [1] (a > >> recent one). Not sure though if there are any available implementations > for > >> it already. > >> > >> [1] > https://www.usenix.org/system/files/conference/atc18/atc18-suresh.pdf > >> > >> пн, 23 нояб. 2020 г. в 10:46, Ivan Daschinsky <ivanda...@gmail.com>: > >> > >>> Also, here is some interesting reading about gossip, SWIM etc. > >>> > >>> 1 -- > >>> http://www.cs.cornell.edu/Info/Projects/Spinglass/public_pdfs/SWIM.pdf > >>> 2 -- > >>> > >>> > http://www.antonkharenko.com/2015/09/swim-distributed-group-membership.html > >>> 3 -- https://github.com/hashicorp/memberlist (Foundation library of > >>> hashicorp serf) > >>> 4 -- https://github.com/scalecube/scalecube-cluster -- (Java > >>> implementation > >>> of SWIM) > >>> > >>> чт, 19 нояб. 2020 г. в 16:35, Ivan Daschinsky <ivanda...@gmail.com>: > >>> > >>> > >> Friday, Nov 27th work for you? If ok, let's have an open call > then. > >>> > Yes, great > >>> > >> As for the protocol port - we will not be dealing with the > >>> > concurrency... > >>> > >>Judging by the Rust port, it seems fairly straightforward. > >>> > Yes, they chose split transport and logic. But original Go package > from > >>> > etcd (see raft/node.go) contains some heartbeats mechanism etc. > >>> > I agree with you, this seems not to be a huge deal to port. > >>> > > >>> > чт, 19 нояб. 2020 г. в 16:13, Alexey Goncharuk < > >>> alexey.goncha...@gmail.com > >>> > >: > >>> > > >>> >> Ivan, > >>> >> > >>> >> Agree, let's have a call to discuss the IEP. I have some more > thoughts > >>> >> regarding how the replication infrastructure works with > >>> >> atomic/transactional caches, will put this info to the IEP. Does > next > >>> >> Friday, Nov 27th work for you? If ok, let's have an open call then. > >>> >> > >>> >> As for the protocol port - we will not be dealing with the > concurrency > >>> >> model if we choose this way, this is what I like about their code > >>> >> structure. Essentially, the raft module is a single-threaded > automata > >>> >> which > >>> >> has a callback to process a message, process a tick (timeout) and > >>> produces > >>> >> messages that should be sent and log entries that should be > persisted. > >>> >> Judging by the Rust port, it seems fairly straightforward. Will be > >>> happy > >>> >> to > >>> >> discuss this and other alternatives on the call as well. > >>> >> > >>> >> чт, 19 нояб. 2020 г. в 14:41, Ivan Daschinsky <ivanda...@gmail.com > >: > >>> >> > >>> >> > > Any existing library that can be used to avoid re-implementing > the > >>> >> > protocol ourselves? Perhaps, porting the existing implementation > to > >>> Java > >>> >> > Personally, I like this idea. Go libraries (either raft module of > >>> etcd > >>> >> or > >>> >> > serf by Hashicorp) are famous for clean code, good design, > >>> stability, > >>> >> not > >>> >> > enormous size. > >>> >> > But, on other side, Go has different model for concurrency and > >>> porting > >>> >> > probably will not be so straightforward. > >>> >> > > >>> >> > > >>> >> > > >>> >> > чт, 19 нояб. 2020 г. в 13:48, Ivan Daschinsky < > ivanda...@gmail.com > >>> >: > >>> >> > > >>> >> > > I'd suggest to discuss this IEP and technical details in open > ZOOM > >>> >> > > meeting. > >>> >> > > > >>> >> > > чт, 19 нояб. 2020 г. в 13:47, Ivan Daschinsky < > >>> ivanda...@gmail.com>: > >>> >> > > > >>> >> > >> > >>> >> > >> > >>> >> > >> ---------- Forwarded message --------- > >>> >> > >> От: Ivan Daschinsky <ivanda...@gmail.com> > >>> >> > >> Date: чт, 19 нояб. 2020 г. в 13:02 > >>> >> > >> Subject: Re: IEP-61 Technical discussion > >>> >> > >> To: Alexey Goncharuk <alexey.goncha...@gmail.com> > >>> >> > >> > >>> >> > >> > >>> >> > >> Alexey, let's arise another question. Specifically, how nodes > >>> >> initially > >>> >> > >> find each other (discovery) and how they detect failures. > >>> >> > >> > >>> >> > >> I suppose, that gossip protocol is an ideal candidate. For > >>> example, > >>> >> > >> consul [1] uses this approach, using serf [2] library to > discover > >>> >> > members > >>> >> > >> of cluster. > >>> >> > >> Then consul forms raft ensemble (server nodes) and client use > >>> raft > >>> >> > >> ensemble only as lock service. > >>> >> > >> > >>> >> > >> PacificA suggests internal heartbeats mechanism for failure > >>> >> detection of > >>> >> > >> replicated group, but it says nothing about initial discovery > of > >>> >> nodes. > >>> >> > >> > >>> >> > >> WDYT? > >>> >> > >> > >>> >> > >> [1] -- https://www.consul.io/docs/architecture/gossip > >>> >> > >> [2] -- https://www.serf.io/ > >>> >> > >> > >>> >> > >> чт, 19 нояб. 2020 г. в 12:46, Alexey Goncharuk < > >>> >> > >> alexey.goncha...@gmail.com>: > >>> >> > >> > >>> >> > >>> Following up the Ignite 3.0 scope/development approach > threads, > >>> >> this is > >>> >> > >>> a separate thread to discuss technical aspects of the IEP. > >>> >> > >>> > >>> >> > >>> Let's reiterate one more time on the questions raised by Ivan > >>> and > >>> >> also > >>> >> > >>> see if there are any other thoughts on the IEP: > >>> >> > >>> > >>> >> > >>> - *Whether to deploy metastorage on a separate subset of > the > >>> >> nodes > >>> >> > >>> or allow Ignite to choose these nodes automatically.* I > >>> think it > >>> >> is > >>> >> > >>> feasible to maintain both modes: by default, Ignite will > >>> choose > >>> >> > >>> metastorage nodes automatically which essentially will > >>> provide > >>> >> the > >>> >> > same > >>> >> > >>> seamless user experience as TCP discovery SPI - no separate > >>> >> roles, > >>> >> > >>> simplistic deployment. For deployments where people want to > >>> have > >>> >> > more > >>> >> > >>> fine-grained control over the nodes' assignments, we will > >>> >> provide a > >>> >> > runtime > >>> >> > >>> configuration which will allow pinning metastorage group to > >>> >> certain > >>> >> > nodes, > >>> >> > >>> thus eliminating the latency concerns. > >>> >> > >>> - *Whether there are any TLA+ specs for the PacificA > >>> protocol.* > >>> >> Not > >>> >> > >>> to my knowledge, but it is known to be used in production > by > >>> >> > Microsoft and > >>> >> > >>> other projects, e.g. [1] > >>> >> > >>> > >>> >> > >>> I would like to collect general feedback on the IEP, as well > as > >>> >> > feedback > >>> >> > >>> on specific parts of it, such as: > >>> >> > >>> > >>> >> > >>> - Metastorage API > >>> >> > >>> - Any existing library that can be used to avoid > >>> re-implementing > >>> >> the > >>> >> > >>> protocol ourselves? Perhaps, porting the existing > >>> implementation > >>> >> to > >>> >> > Java > >>> >> > >>> (the way TiKV did with etcd-raft [2] [3]? This is a very > >>> neat way > >>> >> > btw in my > >>> >> > >>> opinion because I like the finite automata-like approach of > >>> the > >>> >> > replication > >>> >> > >>> module, and, additionally, we could sync bug fixes and > >>> >> improvements > >>> >> > from > >>> >> > >>> the upstream project) > >>> >> > >>> > >>> >> > >>> > >>> >> > >>> Thanks, > >>> >> > >>> --AG > >>> >> > >>> > >>> >> > >>> [1] > >>> >> > >>> > >>> >> > https://cwiki.apache.org/confluence/display/INCUBATOR/PegasusProposal > >>> >> > >>> [2] https://github.com/etcd-io/etcd/tree/master/raft > >>> >> > >>> [3] https://github.com/tikv/raft-rs > >>> >> > >>> > >>> >> > >> > >>> >> > >> > >>> >> > >> -- > >>> >> > >> Sincerely yours, Ivan Daschinskiy > >>> >> > >> > >>> >> > >> > >>> >> > >> -- > >>> >> > >> Sincerely yours, Ivan Daschinskiy > >>> >> > >> > >>> >> > > > >>> >> > > > >>> >> > > -- > >>> >> > > Sincerely yours, Ivan Daschinskiy > >>> >> > > > >>> >> > > >>> >> > > >>> >> > -- > >>> >> > Sincerely yours, Ivan Daschinskiy > >>> >> > > >>> >> > >>> > > >>> > > >>> > -- > >>> > Sincerely yours, Ivan Daschinskiy > >>> > > >>> > >>> > >>> -- > >>> Sincerely yours, Ivan Daschinskiy > >>> > >> > -- Sincerely yours, Ivan Daschinskiy
