{"id":"lsm-flush-double-loss-window","text":"The LSM `_flush()` truncates the WAL after writing an SSTable, but since neither the SSTable write nor the truncation is fsynced, a crash can lose both the WAL source data and the SSTable destination simultaneously — making the data irrecoverable","truth_value":"IN","source":"entries/2026/05/29/topic-bitcask-crash-recovery-guarantees.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"lsm-flush-double-loss-window","truth_value":"IN","reason":"premise"}]}}