Zookeeper hard
By default, `forceSync` is enabled. If you disable it, what trade-off are you making?
- A You gain massive write throughput, but you risk Data Corruption/Loss on power failure because writes are acknowledged before they are physically flushed (fsync) to disk.
- B You lose read throughput.
- C You gain consistency.
- D You disable the Leader.
Answer: A. You gain massive write throughput, but you risk Data Corruption/Loss on power failure because writes are acknowledged before they are physically flushed (fsync) to disk.
Normally, ZK `fsync`s every transaction to the WAL before sending an ACK. Disabling this relies on the OS page cache. If the power cuts, acknowledged transactions vanish.
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