Gate enforcing resource constraints on a setting

This setting will be set by the orchestrator startup process
which is in turn driven by a parameter in the CR.

The default for this is false in the operator so will also be false
in the settings.

Fixes #20163

app/models/miq_worker/container_common.rb

@@ -35,7 +35,7 @@ def resource_constraints
       mem_threshold = self.class.worker_settings[:memory_threshold]
       cpu_threshold = self.class.worker_settings[:cpu_threshold]
 
-      return {} if mem_threshold.nil? && cpu_threshold.nil?
+      return {} if !Settings.server.worker_monitor.enforce_resource_constraints || (mem_threshold.nil? && cpu_threshold.nil?)
 
       {:limits => {}}.tap do |h|
         h[:limits][:memory] = "#{mem_threshold / 1.megabyte}Mi" if mem_threshold

config/settings.yml

@@ -978,6 +978,7 @@
   :worker_messaging_frequency: 5.seconds
   :worker_monitor_frequency: 15.seconds
   :worker_monitor:
+    :enforce_resource_constraints: false
     :kill_algorithm:
       :name: :used_swap_percent_gt_value
       :value: 80

spec/models/miq_worker/container_common_spec.rb

@@ -94,40 +94,53 @@ def deployment_name_for(name)
   end
 
   describe "#resource_constraints" do
-    it "returns an empty hash when no thresholds are set" do
-      allow(MiqGenericWorker).to receive(:worker_settings).and_return({})
-      expect(MiqGenericWorker.new.resource_constraints).to eq({})
-    end
+    context "when allowing resource constraints" do
+      before { stub_settings(:server => {:worker_monitor => {:enforce_resource_constraints => true}}) }
+
+      it "returns an empty hash when no thresholds are set" do
+        allow(MiqGenericWorker).to receive(:worker_settings).and_return({})
+        expect(MiqGenericWorker.new.resource_constraints).to eq({})
+      end
 
-    it "returns the correct hash when both values are set" do
-      allow(MiqGenericWorker).to receive(:worker_settings).and_return(:memory_threshold => 500.megabytes, :cpu_threshold => 500)
-      constraints = {
-        :limits => {
-          :memory => "500Mi",
-          :cpu    => "500m"
+      it "returns the correct hash when both values are set" do
+        allow(MiqGenericWorker).to receive(:worker_settings).and_return(:memory_threshold => 500.megabytes, :cpu_threshold => 500)
+        constraints = {
+          :limits => {
+            :memory => "500Mi",
+            :cpu    => "500m"
+          }
         }
-      }
-      expect(MiqGenericWorker.new.resource_constraints).to eq(constraints)
-    end
+        expect(MiqGenericWorker.new.resource_constraints).to eq(constraints)
+      end
 
-    it "returns only memory when memory is set" do
-      allow(MiqGenericWorker).to receive(:worker_settings).and_return(:memory_threshold => 500.megabytes)
-      constraints = {
-        :limits => {
-          :memory => "500Mi",
+      it "returns only memory when memory is set" do
+        allow(MiqGenericWorker).to receive(:worker_settings).and_return(:memory_threshold => 500.megabytes)
+        constraints = {
+          :limits => {
+            :memory => "500Mi",
+          }
         }
-      }
-      expect(MiqGenericWorker.new.resource_constraints).to eq(constraints)
-    end
+        expect(MiqGenericWorker.new.resource_constraints).to eq(constraints)
+      end
 
-    it "returns only cpu when cpu is set" do
-      allow(MiqGenericWorker).to receive(:worker_settings).and_return(:cpu_threshold => 500)
-      constraints = {
-        :limits => {
-          :cpu => "500m"
+      it "returns only cpu when cpu is set" do
+        allow(MiqGenericWorker).to receive(:worker_settings).and_return(:cpu_threshold => 500)
+        constraints = {
+          :limits => {
+            :cpu => "500m"
+          }
         }
-      }
-      expect(MiqGenericWorker.new.resource_constraints).to eq(constraints)
+        expect(MiqGenericWorker.new.resource_constraints).to eq(constraints)
+      end
+    end
+
+    context "when not allowing resource constraints" do
+      before { stub_settings(:server => {:worker_monitor => {:enforce_resource_constraints => false}}) }
+
+      it "always returns an empty hash" do
+        allow(MiqGenericWorker).to receive(:worker_settings).and_return(:memory_threshold => 500.megabytes, :cpu_threshold => 500)
+        expect(MiqGenericWorker.new.resource_constraints).to eq({})
+      end
     end
   end
 end