{"id":"wal-two-tier-durability-model","text":"The WAL provides two distinct durability levels: individual appends respect the configured sync mode (potentially skipping fsync entirely), while batch operations always force fsync, meaning batch writes are strictly more durable than individual writes regardless of configuration.","truth_value":"IN","source":"","source_url":"","source_hash":"","justifications":[{"type":"SL","antecedents":["sync-mode-none-skips-per-write-fsync","wal-batch-always-fsyncs","force-true-bypasses-sync-mode"],"outlist":[],"label":"The interaction between configurable sync mode and forced batch sync creates an implicit durability hierarchy that callers must understand"}],"dependents":["wal-durability-effective-on-standards-compliant-fsync","wal-durability-tiers-lost-during-recovery"],"metadata":{"last_reviewed":"2026-05-30T09:01:17","review_result":"unnecessary"},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"wal-two-tier-durability-model","truth_value":"IN","reason":"SL justification valid","antecedents":["sync-mode-none-skips-per-write-fsync","wal-batch-always-fsyncs","force-true-bypasses-sync-mode"],"label":"The interaction between configurable sync mode and forced batch sync creates an implicit durability hierarchy that callers must understand"},{"node":"sync-mode-none-skips-per-write-fsync","truth_value":"IN","reason":"premise"},{"node":"wal-batch-always-fsyncs","truth_value":"IN","reason":"premise"},{"node":"force-true-bypasses-sync-mode","truth_value":"IN","reason":"premise"}]}}