Message delivery (at least-once, at most-once, exactly once?) | Messaging in distributed systems
Hello!
After a short break due to the well-known situation, I'm back with the 2nd episode of "Messaging in distributed systems" series. Today, we are going to try to answer a question which at first glance sounds trivial - when message is considered to be delivered? We will try to go through different delivery models, find out what is the ACK and what role it plays in messaging and more importantly we are going to see why exactly once delivery is simply impossible (you will immediately see why I wanted to postpone the premiere of this episode).
Enjoy!
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https://github.com/devmentors/Messagi...
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Timecodes
00:00:00 - Intro
00:01:20 - What is message delivery?
00:03:08 - Message delivery guarantees
00:03:55 - At most-once delivery
00:08:20 - At least-once delivery
00:09:30 - Exactly once delivery?
00:09:50 - Two armies paradox
00:18:35 - What is ACK?
00:23:00 - Prefetch count
00:31:50 - PR merge!
00:33:18 - Code
01:08:45 - Outro