Fix comments

docs/source/reference/config.rst

@@ -3,7 +3,7 @@
 Advanced Configurations
 ===========================
 
-You can pass **optional configuraitions** to SkyPilot in the ``~/.sky/config.yaml`` file.
+You can pass **optional configurations** to SkyPilot in the ``~/.sky/config.yaml`` file.
 
 Such configurations apply to all new clusters and do not affect existing clusters.
 

sky/clouds/cloud.py

@@ -179,7 +179,7 @@ def regions_with_offering(cls, instance_type: str,
 
     @classmethod
     def optimize_by_zone(cls) -> bool:
-        """Returns whether the optimizer by zone."""
+        """Returns whether to optimize this cloud by zone (default: region)."""
         return False
 
     @classmethod

sky/clouds/utils/aws_utils.py

@@ -38,8 +38,6 @@ def list_reservations_for_instance_type(
     if not use_reservations():
         return []
     ec2 = aws.client('ec2', region_name=region)
-    # TODO(zhwu): We need to test the tenancy to make sure the current active
-    # user can consume the reservations.
     response = ec2.describe_capacity_reservations(Filters=[{
         'Name': 'instance-type',
         'Values': [instance_type]

sky/provision/aws/instance.py

@@ -437,6 +437,9 @@ def _create_node_tag(target_instance, is_head: bool = True) -> str:
         created_instances = []
         if target_reservations:
             node_config = copy.deepcopy(config.node_config)
+            # Clear the capacity reservation specification settings in the
+            # original node config, as we will create instances with
+            # reservations with specific settings for each reservation.
             node_config['CapacityReservationSpecification'] = {
                 'CapacityReservationTarget': {}
             }
@@ -459,6 +462,9 @@ def _create_node_tag(target_instance, is_head: bool = True) -> str:
                 reverse=True)
             for reservation, reservation_count in target_reservations_list:
                 if reservation_count <= 0:
+                    # We have sorted the reservations by the available resources,
+                    # so if the reservation is not available, the following
+                    # reservations are not available either.
                     break
                 reservation_count = min(reservation_count, to_start_count)
                 logger.debug(f'Creating {reservation_count} instances '