Fix logging of autoscaling lambda, add test for effective_capacity

tests/ci/autoscale_runners_lambda/app.py

@@ -120,13 +120,13 @@ def set_capacity(
         # Let's calculate a new desired capacity
         # (capacity_deficit + scale_up - 1) // scale_up : will increase min by 1
         # if there is any capacity_deficit
-        desired_capacity = (
+        new_capacity = (
             asg["DesiredCapacity"] + (capacity_deficit + scale_up - 1) // scale_up
         )
-        desired_capacity = max(desired_capacity, asg["MinSize"])
-        desired_capacity = min(desired_capacity, asg["MaxSize"])
+        new_capacity = max(new_capacity, asg["MinSize"])
+        new_capacity = min(new_capacity, asg["MaxSize"])
         # Finally, should the capacity be even changed
-        stop = stop or asg["DesiredCapacity"] == desired_capacity
+        stop = stop or asg["DesiredCapacity"] == new_capacity
         if stop:
             logging.info(
                 "Do not increase ASG %s capacity, current capacity=%s, effective "
@@ -144,9 +144,9 @@ def set_capacity(
             "The ASG %s capacity will be increased to %s, current capacity=%s, "
             "effective capacity=%s, maximum capacity=%s, running jobs=%s, queue size=%s",
             asg["AutoScalingGroupName"],
-            desired_capacity,
-            effective_capacity,
+            new_capacity,
             asg["DesiredCapacity"],
+            effective_capacity,
             asg["MaxSize"],
             running,
             queued,
@@ -154,16 +154,16 @@ def set_capacity(
         if not dry_run:
             client.set_desired_capacity(
                 AutoScalingGroupName=asg["AutoScalingGroupName"],
-                DesiredCapacity=desired_capacity,
+                DesiredCapacity=new_capacity,
             )
         return
 
     # Now we will calculate if we need to scale down
     stop = stop or asg["DesiredCapacity"] == asg["MinSize"]
-    desired_capacity = asg["DesiredCapacity"] - (capacity_reserve // scale_down)
-    desired_capacity = max(desired_capacity, asg["MinSize"])
-    desired_capacity = min(desired_capacity, asg["MaxSize"])
-    stop = stop or asg["DesiredCapacity"] == desired_capacity
+    new_capacity = asg["DesiredCapacity"] - (capacity_reserve // scale_down)
+    new_capacity = max(new_capacity, asg["MinSize"])
+    new_capacity = min(new_capacity, asg["MaxSize"])
+    stop = stop or asg["DesiredCapacity"] == new_capacity
     if stop:
         logging.info(
             "Do not decrease ASG %s capacity, current capacity=%s, effective "
@@ -181,7 +181,7 @@ def set_capacity(
         "The ASG %s capacity will be decreased to %s, current capacity=%s, effective "
         "capacity=%s, minimum capacity=%s, running jobs=%s, queue size=%s",
         asg["AutoScalingGroupName"],
-        desired_capacity,
+        new_capacity,
         asg["DesiredCapacity"],
         effective_capacity,
         asg["MinSize"],
@@ -191,7 +191,7 @@ def set_capacity(
     if not dry_run:
         client.set_desired_capacity(
             AutoScalingGroupName=asg["AutoScalingGroupName"],
-            DesiredCapacity=desired_capacity,
+            DesiredCapacity=new_capacity,
         )
 
 

tests/ci/autoscale_runners_lambda/test_autoscale.py

@@ -35,7 +35,7 @@ class TestSetCapacity(unittest.TestCase):
 
         @property
         def expected_capacity(self) -> int:
-            """one-time property"""
+            """a one-time property"""
             capacity, self._expected_capacity = self._expected_capacity, -1
             return capacity
 
@@ -117,6 +117,33 @@ class TestSetCapacity(unittest.TestCase):
             set_capacity(t.name, t.queues, self.client, False)
             self.assertEqual(t.expected_capacity, self.client.expected_capacity, t.name)
 
+    def test_effective_capacity(self):
+        """Normal cases test increasing w/o considering
+        effective_capacity much lower than DesiredCapacity"""
+        test_cases = (
+            TestCase(
+                "desired-overwritten",
+                1,
+                20,  # DesiredCapacity, overwritten by effective_capacity
+                50,
+                [
+                    Queue("in_progress", 30, "desired-overwritten"),
+                    Queue("queued", 60, "desired-overwritten"),
+                ],
+                40,
+            ),
+        )
+        for t in test_cases:
+            self.client.data_helper(t.name, t.min_size, t.desired_capacity, t.max_size)
+            # we test that effective_capacity is 30 (a half of 60)
+            data_with_instances = self.client.expected_data
+            data_with_instances["AutoScalingGroups"][0]["Instances"] = [
+                {"HealthStatus": "Healthy" if i % 2 else "Unhealthy"} for i in range(60)
+            ]
+            self.client.expected_data = data_with_instances
+            set_capacity(t.name, t.queues, self.client, False)
+            self.assertEqual(t.expected_capacity, self.client.expected_capacity, t.name)
+
     def test_exceptions(self):
         test_cases = (
             (