Comment by toast0

  SEND -->
  SEND -->
       <-- ACK
       <-- ACK (this node was *suuuper* slow due to page thrashing.)

Don't try to "fix" it, either; there's no way to do that.

You make the job idempotent, in some manner: make it such that receiving the message and processing it twice is safe.

(This is what TFA eventually capitulates to, but tries to call it "exactly once delivery", even in cases where deliver is occurring more than once. I don't think this view is pedagogically useful, which is partly why we say "exactly once delivery is impossible.")

Filligree 6 hours ago

You keep sending it until you get an acknowledgement back. As the article points out, this does assume nobody cut the wire.

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deathanatos 5 hours ago
SEND --> SEND --> <-- ACK <-- ACK (this node was *suuuper* slow due to page thrashing.)
Don't try to "fix" it, either; there's no way to do that.
You make the job idempotent, in some manner: make it such that receiving the message and processing it twice is safe.
(This is what TFA eventually capitulates to, but tries to call it "exactly once delivery", even in cases where deliver is occurring more than once. I don't think this view is pedagogically useful, which is partly why we say "exactly once delivery is impossible.")
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