alt Hacker NewsI don't know about Jetstream, but redis cluster would only ack writes after replicating to a majority of nodes. I think there is some config on standalone redis too where you can ack after fsync (which apparently still doesn't guarantee anything because of buffering in the OS). In any case, understanding what the ack implies is important, and I'd be frustrated if jetstream docs were not clear on that.
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sk5t • yesterday at 1:35 AM
To the best of my knowledge, Redis has never blocked for replication, although you can configure healthy replication state as a prerequisite to accept writes.
At least per the Redis docs, clusters acknowledge writes before they're replicated: https://redis.io/docs/latest/operate/oss_and_stack/managemen...
The docs explicitly state that clusters do not provide strong consistency and can lose acknowledged data.