{"id":"wal-batch-mode-loses-up-to-n-records","text":"In WAL batch sync mode, up to `batch_sync_count - 1` records (default 99) can be lost on `kill -9` because `os.fsync()` is deferred until the batch threshold is reached; only `append_batch()` force-fsyncs regardless of mode.","truth_value":"IN","source":"entries/2026/05/29/topic-crash-recovery-invariants.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"wal-batch-mode-loses-up-to-n-records","truth_value":"IN","reason":"premise"}]}}