[Autoscaler] Account for resource backlog size (#11261)

python/ray/tests/test_monitor.py

@@ -0,0 +1,39 @@
+import ray
+from ray.monitor import parse_resource_demands
+
+
+def test_parse_resource_demands():
+    resource_load_by_shape = ray.gcs_utils.ResourceLoad(resource_demands=[
+        ray.gcs_utils.ResourceDemand(
+            shape={"CPU": 1},
+            num_ready_requests_queued=1,
+            num_infeasible_requests_queued=0,
+            backlog_size=0),
+        ray.gcs_utils.ResourceDemand(
+            shape={"CPU": 2},
+            num_ready_requests_queued=1,
+            num_infeasible_requests_queued=0,
+            backlog_size=1),
+        ray.gcs_utils.ResourceDemand(
+            shape={"CPU": 3},
+            num_ready_requests_queued=0,
+            num_infeasible_requests_queued=1,
+            backlog_size=2),
+        ray.gcs_utils.ResourceDemand(
+            shape={"CPU": 4},
+            num_ready_requests_queued=1,
+            num_infeasible_requests_queued=1,
+            backlog_size=2),
+    ])
+
+    waiting, infeasible = \
+        parse_resource_demands(resource_load_by_shape)
+
+    assert waiting.count({"CPU": 1}) == 1
+    assert waiting.count({"CPU": 2}) == 2
+    assert infeasible.count({"CPU": 3}) == 3
+    # The {"CPU": 4} case here is inconsistent, but could happen. Since the
+    # heartbeats are eventually consistent, we won't worry about whether it's
+    # counted as infeasible or waiting, as long as it's accounted for and
+    # doesn't cause an error.
+    assert len(waiting + infeasible) == 10