{"id":"two-wal-designs-in-repo","text":"The standalone `wal.py` uses a logical WAL (keyed PUT/DELETE operations with COMMIT markers) while `btree.py` uses a physical WAL (raw page images); they solve different problems and have different recovery semantics","truth_value":"IN","source":"entries/2026/05/29/topic-write-ahead-logging-fsync-ordering.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"two-wal-designs-in-repo","truth_value":"IN","reason":"premise"}]}}