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jvanlightlyon S3 Express One Zone, not quite what I hoped for

Author here: Regarding point 3, it was my understanding that inserts are synchronous but updates may be asynchronous. Is that the case?

jvanlightlyon Why `fsync()`: Losing unsynced data on a single node leads to global data loss

Protocol Aware Recovery is really needed if you want Raft to tolerate disk corruption. https://www.usenix.org/conference/fast18/presentation/alagap...

jvanlightlyon Kafka vs. Redpanda performance – do the claims add up?

These instances can manage up disk throughput up to 2 GB/s (400K IOPS) and network throughout of 25gbps or ~3.1 GB/s.

There are so many dimensions, with configurations, CPU architecture, hardware resources plus all the workloads and the client configs. It gets kind of crazy. I like to use a dimension testing approach where I fix everything but vary one or possibly two dimensions at a time and plot the relationships to performance.

jvanlightlyon Kafka vs. Redpanda performance – do the claims add up?

It's a common misconception about Kafka and fsyncs. But the Kafka replication protocol has a recovery mechanism, much in the same way that Viewstamped Replication Revisited does (except it's safer due to the page cache), which allows Kafka to write to disk asynchronously. The trade-off is that we need fault domains (AZs in the cloud), but if we care about durability and availability, we should be deploying across AZs anyway. We've seen plenty of full region outages, but zero power loss events in multiple AZs in six years.

Kafka and fsyncs: https://jack-vanlightly.com/blog/2023/4/24/why-apache-kafka-...

jvanlightlyon Kafka vs. Redpanda performance – do the claims add up?

Well, that just isn't accurate really. Kafka would need simulteanous VM failure across all AZs. That just doesn't happen in the real world often enough to worry about. It has never happened in Confluent Cloud. RP have a similar issue. Single AZ deployments with local NVMe drives. AZ loses power, a majority of brokers could lose all their data. Then there's data corruption. Fsyncs alone don't save you. The next step would be to implement Protocol Aware Recovery (https://www.usenix.org/conference/fast18/presentation/alagap...) like TigerBeetle have. Does a system that has implemented anti-corruption in the storage layer now get to lambast Redpanda, Pulsar, ZooKeeper etc because they didn't implement that?

jvanlightlyon Kafka vs. Redpanda performance – do the claims add up?

Author here. Anyone can run these tests. It's available for anyone to run and check my results.

jvanlightlyon Kafka vs. Redpanda performance – do the claims add up?

Author here. Yes both Kafka and Redpanda were deployed on identical hardware: three i3en.6xlarge.