5 ms·

When a leader fails, does a publisher confirm guarantee the message survived on at least one follower?

• deleted 5mo ago
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• deleted 5mo ago
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• abaelter 5mo ago
  I'm Anders, a LavinMQ-core developer. We send the confirm as soon as the message hits the mmap and is appended to the local replication queue because that keeps publish latency at memory-copy speed, and the loss window is narrow: only messages still in the page cache or sitting in the replication queue when the leader dies. Config options are coming to opt into stronger guarantees (msync on the leader, waiting for follower ack, or follower fsync), at the cost of added latency.
  • yxhuvud 5mo ago
    Could it be worth looking into the Raft algorithm?
    • CarlHoerberg 5mo ago
      Yes, we do use raft for leader election
  • jhk482001 5mo ago
    Hi Anders, thank you for the clarity! That make sense, it sounds like the "publisher confirm" feature for RabbitMQ that we used before! And it's good to know the stronger options are coming :D