Mention at which step did the best value happen

bob/learn/tensorflow/utils/hooks.py

@@ -141,6 +141,7 @@ class EarlyStopping(tf.train.SessionRunHook):
         # Allow instances to be re-used
         self.wait = 0
         self.best = np.Inf if self.monitor_op == np.less else -np.Inf
+        self.global_step_of_best = 0
 
     def begin(self):
         self.values = []
@@ -148,26 +149,36 @@ class EarlyStopping(tf.train.SessionRunHook):
             self.monitor = _as_graph_element(self.monitor)
         else:
             self.monitor = _as_graph_element(self.monitor.name)
+        self.global_step_tensor = tf.train.get_global_step()
 
     def before_run(self, run_context):
-        return tf.train.SessionRunArgs(self.monitor)
+        return tf.train.SessionRunArgs([self.monitor, self.global_step_tensor])
 
     def after_run(self, run_context, run_values):
-        self.values.append(run_values.results)
+        monitor, global_step = run_values.results
+        self.values.append(monitor)
+        # global step does not change during evaluation so keeping one of them
+        # is enough.
+        self.global_step_value = global_step
 
     def _should_stop(self):
         current = np.mean(self.values)
-        logger.info('%s is currently at %f and the best value was %f',
-                    self.monitor.name, current, self.best)
+        logger.info(
+            '%s is currently at %f (at step of %d) and the best value was %f '
+            '(at step of %d)', self.monitor.name, current,
+            self.global_step_value, self.best, self.global_step_of_best)
         if self.monitor_op(current - self.min_delta, self.best):
             self.best = current
             self.wait = 0
+            self.global_step_of_best = self.global_step_value
         else:
             if self.wait >= self.patience:
-                raise EarlyStopException(
-                    'Early stopping happened with {} at best of '
-                    '{} and current of {}'.format(
-                        self.monitor, self.best, current))
+                message = 'Early stopping happened with {} at best of ' \
+                    '{} (at step {}) and current of {} (at step {})'.format(
+                        self.monitor.name, self.best, self.global_step_of_best,
+                        current, self.global_step_value)
+                logger.info(message)
+                raise EarlyStopException(message)
             self.wait += 1
 
     def end(self, session):