[tune] use dated experiment dir per default (#11104)

python/ray/tune/suggest/basic_variant.py

@@ -77,7 +77,7 @@ class BasicVariantGenerator(SearchAlgorithm):
                 self._trial_generator,
                 self._generate_trials(
                     experiment.spec.get("num_samples", 1), experiment.spec,
-                    experiment.name))
+                    experiment.dir_name))
 
     def next_trial(self):
         """Provides one Trial object to be queued into the TrialRunner.

python/ray/tune/suggest/search_generator.py

@@ -111,7 +111,7 @@ class SearchGenerator(SearchAlgorithm):
         """
         if not self.is_finished():
             return self.create_trial_if_possible(self._experiment.spec,
-                                                 self._experiment.name)
+                                                 self._experiment.dir_name)
         return None
 
     def create_trial_if_possible(self, experiment_spec: Dict,