diff --git a/streaming/base/dataset.py b/streaming/base/dataset.py
index e4b7d1cfd..02b374e28 100644
--- a/streaming/base/dataset.py
+++ b/streaming/base/dataset.py
@@ -3,6 +3,7 @@
 
 """A mid-epoch-resumable streaming/caching pytorch IterableDataset."""
 
+import getpass
 import json
 import logging
 import os
@@ -495,7 +496,7 @@ def __init__(self,
         ]
         self._shm_prefix_int, self._locals_shm = get_shm_prefix(streams_local, streams_remote,
                                                                 world)
-        self._filelock_root = os.path.join(os.path.sep, 'tmp', 'streaming')
+        self._filelock_root = os.path.join(os.path.sep, 'tmp', getpass.getuser(), 'streaming')
         os.makedirs(self._filelock_root, exist_ok=True)
 
         # Create the shared memory-backed barrier, without its lock, which is unpickleable.
diff --git a/streaming/base/shared/prefix.py b/streaming/base/shared/prefix.py
index 48d2aaa6c..3ae33144f 100644
--- a/streaming/base/shared/prefix.py
+++ b/streaming/base/shared/prefix.py
@@ -7,6 +7,7 @@
 prevent shared resources like shared memory from colliding.
 """
 
+import getpass
 from collections import Counter
 from time import sleep
 from typing import Iterator, List, Tuple, Union
@@ -41,7 +42,7 @@ def _get_path(prefix_int: int, name: str) -> str:
     Returns:
         str: Unique shared memory name.
     """
-    return f'{prefix_int:06}_{name}'
+    return f'{getpass.getuser()}_{prefix_int:06}_{name}'
 
 
 def _pack_locals(dirnames: List[str], prefix_int: int) -> bytes: