Comment by zenoprax

2 hours ago

Where is the "data loss window"? Between nodes or between the client and the infra?

The front page lists under Capabilities:

> 4.8 > Honest fsync > A successful fsync means every acknowledged write is durable in S3. If a failover may have lost unflushed writes, the next fsync returns an error instead of a false success.

Someone else mentioned: "write() is buffered (that's the batching) and "committed" maps to fsync(), which returns only once data is durable."

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It sounds like all writes are written synchronously to at least one node but failovers/replicas are just eventually consistent. If so, latency between nodes is not within ZeroFS's control and including. Or are you saying that the latency is impossible for even a single node? If so, that would mean much more than just a footnote is needed.

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I don't see an issue with the benchmark but I might not be looking in the right place.

The [sequential writes](https://github.com/Barre/ZeroFS/blob/ec32199d48d0409d4cccd44...) and [append-only writes](https://github.com/Barre/ZeroFS/blob/ec32199d48d0409d4cccd44...) start where I'd expect and `success: true,` should equate to `fsync()` as previously mentioned.