feat(kafka): Sharding into many topics based on partition key #4861
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untitaker
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Jun 26, 2025
| @@ -112,7 +112,6 @@ ed25519-dalek = "2.1.1" | |||
| enumset = "1.0.13" | |||
| flate2 = "1.0.35" | |||
| flume = { version = "0.11.1", default-features = false } | |||
| fnv = "1.0.7" | |||
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fnv was entirely unused
relay-kafka/src/producer/mod.rs
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| None => { | ||
| // fetch_add wraps on overflow | ||
| let count = self.round_robin_counter.fetch_add(1, Ordering::Relaxed); | ||
| count % self.topic_producers.len() |
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i think doing round-robin between shards in case of no key is probably cheaper than actually-random, wdyt
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Dav1dde
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Jun 26, 2025
| Inner::ShardedSecondary(configs) => configs, | ||
| }; | ||
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| Ok(Self(configs)) |
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We should guard somewhere against empty lists, can be here or in the config conversion to the Kafka* types.
Dav1dde
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Jun 27, 2025
Co-authored-by: David Herberth <[email protected]>
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Introduce sharding into the kafka producer, even with shards distributed across many brokers.
We could've had a different implementation where we have a ShardingProducer wrapping many Producers, but while this would avoid touching the most critical parts of the codebase, it would also mean a ton of additional code. I think it's cleaner to work towards a design where non-sharded topics are a special case of sharded topics.
ref RELAY-115