feat(cadence-matching): simplify the load calculation for shards

service/matching/tasklist/interfaces.go

@@ -75,6 +75,7 @@ type (
 		UpdateTaskListPartitionConfig(context.Context, *types.TaskListPartitionConfig) error
 		RefreshTaskListPartitionConfig(context.Context, *types.TaskListPartitionConfig) error
 		LoadBalancerHints() *types.LoadBalancerHints
+		QueriesPerSecond() float64
 		ReleaseBlockedPollers() error
 	}
 

service/matching/tasklist/shard_processor.go

@@ -107,10 +107,8 @@ func (sp *shardProcessorImpl) getShardLoad() float64 {
 	// we need to sum the rps for each of the tasklist to calculate the load.
 	for _, tlMgr := range sp.taskLists {
 		if tlMgr.TaskListID().name == sp.shardID {
-			lbh := tlMgr.LoadBalancerHints()
-			if lbh != nil {
-				load = load + lbh.RatePerSecond
-			}
+			qps := tlMgr.QueriesPerSecond()
+			load = load + qps
 		}
 	}
 	return load

service/matching/tasklist/task_list_manager.go

@@ -398,6 +398,10 @@ func (c *taskListManagerImpl) LoadBalancerHints() *types.LoadBalancerHints {
 	}
 }
 
+func (c *taskListManagerImpl) QueriesPerSecond() float64 {
+	return c.qpsTracker.QPS()
+}
+
 func isTaskListPartitionConfigEqual(a types.TaskListPartitionConfig, b types.TaskListPartitionConfig) bool {
 	a.Version = b.Version
 	return reflect.DeepEqual(a, b)

service/matching/tasklist/task_list_manager_test.go

@@ -454,6 +454,46 @@ func TestDescribeTaskList(t *testing.T) {
 	}
 }
 
+func TestQueriesPerSecond(t *testing.T) {
+	testCases := []struct {
+		name        string
+		mockSetup   func(ctrl *gomock.Controller, tlm *taskListManagerImpl)
+		expectedQPS float64
+	}{
+		{
+			name: "returns QPS from tracker",
+			mockSetup: func(ctrl *gomock.Controller, tlm *taskListManagerImpl) {
+				mockQPS := stats.NewMockQPSTrackerGroup(ctrl)
+				mockQPS.EXPECT().QPS().Return(float64(42.5))
+				tlm.qpsTracker = mockQPS
+			},
+			expectedQPS: 42.5,
+		},
+		{
+			name: "returns zero QPS",
+			mockSetup: func(ctrl *gomock.Controller, tlm *taskListManagerImpl) {
+				mockQPS := stats.NewMockQPSTrackerGroup(ctrl)
+				mockQPS.EXPECT().QPS().Return(float64(0))
+				tlm.qpsTracker = mockQPS
+			},
+			expectedQPS: 0,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			ctrl := gomock.NewController(t)
+			logger := testlogger.New(t)
+			tlm := createTestTaskListManager(t, logger, ctrl)
+
+			tc.mockSetup(ctrl, tlm)
+
+			actualQPS := tlm.QueriesPerSecond()
+			assert.Equal(t, tc.expectedQPS, actualQPS)
+		})
+	}
+}
+
 func TestCheckIdleTaskList(t *testing.T) {
 	defer goleak.VerifyNone(t)
 	cfg := config.NewConfig(dynamicconfig.NewNopCollection(), "some random hostname", commonConfig.RPC{}, getIsolationgroupsHelper)