These are chat archives for atomix/atomix

3rd
Oct 2016
Jon Hall
@jhall11
Oct 03 2016 16:33

Are append requests supposed to be sent to UNAVAILABLE members?

In answer to my own question, it appears these messages are being sent as part of the heartbeat

Jordan Halterman
@kuujo
Oct 03 2016 17:11
Right... This is part of the Raft algorithm. The leader sends append requests to followers even when it has no entries to send since they act as heartbeats. When the leader knows a follower to be UNAVAILABLE, it will still send those heartbeats to that follower so it can determine when it's reachable again, but the leader will send empty append requests so it's not unnecessarily reading from disk to send stuff that will never make it anyways. Once the leader receives a successful response it will start sending non-empty requests if possible again.