pub fn spawn_bg_writer(
buffer_pool: Arc<dyn BufferMaintenance>,
interval: Option<Duration>,
vacuum_cfg: IndexVacuumConfig,
) -> Option<WorkerHandle>pub fn spawn_bg_writer(
buffer_pool: Arc<dyn BufferMaintenance>,
interval: Option<Duration>,
vacuum_cfg: IndexVacuumConfig,
) -> Option<WorkerHandle>