Run garbage collector between batches.

tf_shell_ml/model_base.py

@@ -19,6 +19,7 @@
 import tf_shell
 import tf_shell_ml
 import time
+import gc
 
 
 class SequentialBase(keras.Sequential):
@@ -213,6 +214,8 @@ def fit(
             features_dataset, labels_dataset = self.prep_dataset_for_model(
                 features_dataset, labels_dataset
             )
+            tf.keras.backend.clear_session()
+            gc.collect()
 
         # Calculate samples if possible.
         if steps_per_epoch is None:
@@ -251,6 +254,7 @@ def fit(
                 callback_list.on_train_batch_begin(step, logs)
                 logs, num_slots = self.train_step_tf_func(batch_x, batch_y)
                 callback_list.on_train_batch_end(step, logs)
+                gc.collect()
                 if steps_per_epoch is not None and step + 1 >= steps_per_epoch:
                     break