![[assets/wl_io_logicalrewritecheckpointsync.png|256]] - **Description**: Waiting for logical rewrite mappings to be flushed to disk during a checkpoint. This wait indicates the backend is executing a direct OS `fsync()` or `fdatasync()` system call, forcing the filesystem's dirty block cache to be physically persisted to the storage device. - **Resources**: [[Resources/disk IO]], [[Resources/CPU|CPU]]