Configuration

Environment variables and runtime tuning.

SwanLake loads settings from environment variables with the SWANLAKE_ prefix.

Core Server

VariableDefaultPurpose
SWANLAKE_HOST0.0.0.0gRPC bind address
SWANLAKE_PORT4214gRPC listen port
SWANLAKE_MAX_SESSIONS100Max concurrent sessions
SWANLAKE_SESSION_TIMEOUT_SECONDS900Idle session cleanup timeout
SWANLAKE_SESSION_ID_MODEpeer_addrSession identifier mode

Status and Metrics

VariableDefaultPurpose
SWANLAKE_STATUS_ENABLEDtrueEnable status HTTP server
SWANLAKE_STATUS_HOST0.0.0.0Status bind address
SWANLAKE_STATUS_PORT4215Status port
SWANLAKE_METRICS_SLOW_QUERY_THRESHOLD_MS5000Slow query threshold
SWANLAKE_METRICS_HISTORY_SIZE200Metrics history retention

DuckLake and DuckDB

VariableDefaultPurpose
SWANLAKE_DUCKLAKE_INIT_SQL(unset)SQL to run after DuckDB startup
SWANLAKE_DUCKDB_THREADSDuckDB defaultOverride execution thread count

Maintenance Checkpointing

VariableDefaultPurpose
SWANLAKE_CHECKPOINT_DATABASES(unset)Comma-separated DB list
SWANLAKE_CHECKPOINT_INTERVAL_HOURS24Checkpoint interval
SWANLAKE_CHECKPOINT_POLL_SECONDS300Poll interval

For the full and most up-to-date list, see CONFIGURATION.md.


Last modified February 21, 2026: swanlake (7ab91c8)