Object Spilling =============== .. _object-spilling: Ray spills objects to a directory in the local filesystem once the object store is full. By default, Ray spills objects to the temporary directory (for example, ``/tmp/ray/session_2025-03-28_00-05-20_204810_2814690``). Spilling to a custom directory ------------------------------- You can specify a custom directory for spilling objects by setting the ``object_spilling_directory`` parameter in the ``ray.init`` function or the ``--object-spilling-directory`` command line option in the ``ray start`` command. .. tab-set:: .. tab-item:: Python .. doctest:: ray.init(object_spilling_directory="/path/to/spill/dir") .. tab-item:: CLI .. doctest:: ray start --object-spilling-directory=/path/to/spill/dir For advanced usage and customizations, reach out to the `Ray team `_. Stats ----- When spilling is happening, the following INFO level messages are printed to the Raylet logs-for example, ``/tmp/ray/session_latest/logs/raylet.out``:: local_object_manager.cc:166: Spilled 50 MiB, 1 objects, write throughput 230 MiB/s local_object_manager.cc:334: Restored 50 MiB, 1 objects, read throughput 505 MiB/s You can also view cluster-wide spill stats by using the ``ray memory`` command:: --- Aggregate object store stats across all nodes --- Plasma memory usage 50 MiB, 1 objects, 50.0% full Spilled 200 MiB, 4 objects, avg write throughput 570 MiB/s Restored 150 MiB, 3 objects, avg read throughput 1361 MiB/s If you only want to display cluster-wide spill stats, use ``ray memory --stats-only``.