Create copies of Pathways arrays before starting the serialization in orbax handler.

This prevents the buffers from being deallocated if the user discards the array before the asynchronous save operation completes.

PiperOrigin-RevId: 766470507

Author: mridul-sahu

pathwaysutils/elastic/README.md

@@ -87,10 +87,15 @@ async def serialize(
     if any([arg.dtype is not None for arg in args]):
       raise ValueError("Casting during save not supported for Pathways.")
 
+    # Create a copy of the arrays to ensure their buffers are not deallocated
+    # before the asynchronous write operation completes.
+    copied_values = [v.copy() for v in values]
+    jax.block_until_ready(copied_values)
+
     locations, names = extract_parent_dir_and_name(infos)
     return [
         future.CommitFutureAwaitingContractedSignals(
-            self._background_serialize(values, locations, names),
+            self._background_serialize(copied_values, locations, names),
             name="cloud_pathways_array_handler",
         )
     ]