Details
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Task
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Status: Resolved
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Normal
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Resolution: Fixed
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None
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Semantic
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Normal
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All
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Description
About the documentation on commit logs:
- Commit logs default is every 10 sec - periodic, not batch https://github.com/apache/cassandra/blob/cassandra-3.11.8/conf/cassandra.yaml#L385-L386 (same in 3.11.9 or trunk). It can lead to data losses but still makes sense to me because fsync-ing every write is very expensive, and (even in batches) should be reserved for the super paranoid where handling multiple power-out (or sudden disk failures) simultaneously on multiple nodes needs to be handled (as Michael Semb Wever explained to me).
* Nonetheless, apart from the theory behind it, in a more practical perspective, the doc is wrong and says Default Value: batch which mislead me and this could happen to more people: https://cassandra.apache.org/doc/latest/architecture/storage_engine.html#commit-log
I think this is important enough for us to quickly fix the documentation in trunk. As this information is fully missing in the 3.11 branch documentation, I suggest we add it as well on that branch (based on information about commit logs from trunk).