Change MLFLOW_ENABLE_TRACE_IN_SERVING default value to False (mlflo…

…w#12095)

Signed-off-by: harupy <17039389+harupy@users.noreply.github.com>

mlflow/environment_variables.py

@@ -579,9 +579,12 @@ def get(self):
 # How many traces to be buffered at the in-memory trace client.
 MLFLOW_TRACE_BUFFER_MAX_SIZE = _EnvironmentVariable("MLFLOW_TRACE_BUFFER_MAX_SIZE", int, 1000)
 
-# Whether or not to enable trace logging in MLflow in served models.
-# TODO: Document the behavior of this flag.
-MLFLOW_ENABLE_TRACE_IN_SERVING = _BooleanEnvironmentVariable("MLFLOW_ENABLE_TRACE_IN_SERVING", True)
+#: Whether or not to enable trace logging in model serving.
+#: The default value is set to False to ensure that this flag is only enabled
+#: when our internal safety mechanism on Databricks explicitly sets it to True.
+MLFLOW_ENABLE_TRACE_IN_SERVING = _BooleanEnvironmentVariable(
+    "MLFLOW_ENABLE_TRACE_IN_SERVING", False
+)
 
 # Whether to use presigned URLs to interact with the Unity Catalog
 MLFLOW_UNITY_CATALOG_PRESIGNED_URLS_ENABLED = _BooleanEnvironmentVariable(