diff --git a/cacheflow/utils.py b/cacheflow/utils.py
new file mode 100644
index 0000000000000..485e18f6d37eb
--- /dev/null
+++ b/cacheflow/utils.py
@@ -0,0 +1,20 @@
+import enum
+
+
+class Device(enum.Enum):
+    GPU = enum.auto()
+    CPU = enum.auto()
+
+
+class Counter:
+
+    def __init__(self, start: int = 0) -> None:
+        self.counter = start
+
+    def next(self) -> int:
+        id = self.counter
+        self.counter += 1
+        return id
+
+    def reset(self) -> None:
+        self.counter = 0