[GitHub] nickva opened a new pull request #838: Do not buffer rexi messages to disconnected nodes

[gi...@git.apache.org]

nickva opened a new pull request #838: Do not buffer rexi messages to disconnected nodes
URL: https://github.com/apache/couchdb/pull/838
 
 
   Instead wait 15 seconds after last cluster configuration change, if there
   were no more changes to the cluster, stop rexi buffers and servers for nodes
   which are no longer connected.
   
   Extract and reuse cluster stability check from `couch_replicator_clustering`
   and move it to `mem3_cluster` module, so both replicator and rexi can use it.
   Users of `mem3_cluster` would implement a behavior callback API then spawn_link
   the cluster monitor with their specific period values.
   
   This also simplifies the logic in rexi_server_mon as it no longer needs to
   handle `{nodeup, _}` and `{nodedown, _}` messages. On any cluster membership
   change it will get a `cluster_unstable` message. It then immediately spawns new
   servers and buffers if needed. Only when cluster has stabilized it will stop
   servers and buffers for disconnected nodes. The idea is to allow for short
   periods of disconnects between nodes before throwing away all the buffered
   messages.
   
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