[core] Supress infeasible warning (#14068)

doc/source/placement-group.rst

@@ -162,6 +162,12 @@ Let's create a placement group. Recall that each bundle is a collection of resou
   # Wait until placement group is created.
   ray.get(pg.ready())
 
+ .. note::
+
+    When using placement groups, users should ensure that their placement groups are ready (by calling ``ray.get(pg.ready())``)
+    and have the proper resources. Ray assumes that the placement group will be properly created and does *not*
+    print a warning about infeasible tasks.
+
 Now let's define an actor that uses GPU. We'll also define a task that use ``extra_resources``.
 
 .. code-block:: python
@@ -229,7 +235,7 @@ because they are scheduled on a placement group with the STRICT_PACK strategy.
         # scheduled with the parent's placement group.
         ray.get(child.options(placement_group=None).remote())
 
-Note that you can anytime remove the placement group to clean up resources.
+You can remove a placement group at any time to free its allocated resources.
 
 .. code-block:: python
 

python/ray/tests/test_failure.py

@@ -15,6 +15,7 @@ import ray
 from ray.experimental.internal_kv import _internal_kv_get
 from ray.autoscaler._private.util import DEBUG_AUTOSCALING_ERROR
 import ray.utils
+from ray.util.placement_group import placement_group
 import ray.ray_constants as ray_constants
 from ray.exceptions import RayTaskError
 from ray.cluster_utils import Cluster
@@ -707,6 +708,15 @@ def test_warning_for_infeasible_tasks(ray_start_regular, error_pubsub):
     assert len(errors) == 1
     assert errors[0].type == ray_constants.INFEASIBLE_TASK_ERROR
 
+    # Placement group cannot be made, but no warnings should occur.
+    pg = placement_group([{"GPU": 1}], strategy="STRICT_PACK")
+    pg.ready()
+    f.options(placement_group=pg).remote()
+
+    errors = get_error_message(
+        p, 1, ray_constants.INFEASIBLE_TASK_ERROR, timeout=5)
+    assert len(errors) == 0, errors
+
 
 def test_warning_for_infeasible_zero_cpu_actor(shutdown_only):
     # Check that we cannot place an actor on a 0 CPU machine and that we get an

python/ray/util/placement_group.py

@@ -109,9 +109,7 @@ class PlacementGroup:
         return len(self.bundle_cache)
 
     def _get_none_zero_resource(self, bundle: List[Dict]):
-        # This number shouldn't be changed.
-        # When it is specified, node manager won't warn about infeasible
-        # tasks.
+        # Any number between 0-1 should be fine.
         INFEASIBLE_TASK_SUPPRESS_MAGIC_NUMBER = 0.0101
         for key, value in bundle.items():
             if value > 0:

src/ray/raylet/node_manager.cc

@@ -2156,18 +2156,11 @@ void NodeManager::RecordMetrics() {
 }
 
 void NodeManager::PublishInfeasibleTaskError(const Task &task) const {
-  // This block is used to suppress infeasible task warning.
   bool suppress_warning = false;
-  const auto &required_resources = task.GetTaskSpecification().GetRequiredResources();
-  const auto &resources_map = required_resources.GetResourceMap();
-  const auto &it = resources_map.begin();
-  // It is a hack to suppress infeasible task warning.
-  // If the first resource of a task requires this magic number, infeasible warning is
-  // suppressed. It is currently only used by placement group ready API. We don't want
-  // to have this in ray_config_def.h because the use case is very narrow, and we don't
-  // want to expose this anywhere.
-  double INFEASIBLE_TASK_SUPPRESS_MAGIC_NUMBER = 0.0101;
-  if (it != resources_map.end() && it->second == INFEASIBLE_TASK_SUPPRESS_MAGIC_NUMBER) {
+
+  if (!task.GetTaskSpecification().PlacementGroupBundleId().first.IsNil()) {
+    // If the task is part of a placement group, do nothing. If necessary, the infeasible
+    // warning should come from the placement group scheduling, not the task scheduling.
     suppress_warning = true;
   }