Take init containers into account when getting pod resource request

pkg/scheduler/api/job_info.go

@@ -61,12 +61,7 @@ func getJobID(pod *v1.Pod) JobID {
 }
 
 func NewTaskInfo(pod *v1.Pod) *TaskInfo {
-	req := EmptyResource()
-
-	// TODO(k82cn): also includes initContainers' resource.
-	for _, c := range pod.Spec.Containers {
-		req.Add(NewResource(c.Resources.Requests))
-	}
+	req := getResourceRequest(pod)
 
 	jobID := getJobID(pod)
 
@@ -89,6 +84,45 @@ func NewTaskInfo(pod *v1.Pod) *TaskInfo {
 	return ti
 }
 
+// Refer k8s.io/kubernetes/pkg/scheduler/algorithm/predicates/predicates.go#GetResourceRequest.
+//
+// GetResourceRequest returns a *Resource that covers the largest width in each resource dimension.
+// Because init-containers run sequentially, we collect the max in each dimension iteratively.
+// In contrast, we sum the resource vectors for regular containers since they run simultaneously.
+//
+// Example:
+//
+// Pod:
+//   InitContainers
+//     IC1:
+//       CPU: 2
+//       Memory: 1G
+//     IC2:
+//       CPU: 2
+//       Memory: 3G
+//   Containers
+//     C1:
+//       CPU: 2
+//       Memory: 1G
+//     C2:
+//       CPU: 1
+//       Memory: 1G
+//
+// Result: CPU: 3, Memory: 3G
+func getResourceRequest(pod *v1.Pod) *Resource {
+	result := EmptyResource()
+	for _, container := range pod.Spec.Containers {
+		result.Add(NewResource(container.Resources.Requests))
+	}
+
+	// take max_resource(sum_pod, any_init_container)
+	for _, container := range pod.Spec.InitContainers {
+		result.SetMaxResource(NewResource(container.Resources.Requests))
+	}
+
+	return result
+}
+
 func (ti *TaskInfo) Clone() *TaskInfo {
 	return &TaskInfo{
 		UID:         ti.UID,

pkg/scheduler/api/job_info_test.go

@@ -195,3 +195,72 @@ func TestDeleteTaskInfo(t *testing.T) {
 		}
 	}
 }
+
+func TestGetResourceRequest(t *testing.T) {
+	tests := []struct {
+		name             string
+		pod              *v1.Pod
+		expectedResource *Resource
+	}{
+		{
+			name: "get resource for pod without init containers",
+			pod: &v1.Pod{
+				Spec: v1.PodSpec{
+					Containers: []v1.Container{
+						{
+							Resources: v1.ResourceRequirements{
+								Requests: buildResourceList("1000m", "1G"),
+							},
+						},
+						{
+							Resources: v1.ResourceRequirements{
+								Requests: buildResourceList("2000m", "1G"),
+							},
+						},
+					},
+				},
+			},
+			expectedResource: NewResource(buildResourceList("3000m", "2G")),
+		},
+		{
+			name: "get resource for pod with init containers",
+			pod: &v1.Pod{
+				Spec: v1.PodSpec{
+					InitContainers: []v1.Container{
+						{
+							Resources: v1.ResourceRequirements{
+								Requests: buildResourceList("2000m", "5G"),
+							},
+						},
+						{
+							Resources: v1.ResourceRequirements{
+								Requests: buildResourceList("2000m", "1G"),
+							},
+						},
+					},
+					Containers: []v1.Container{
+						{
+							Resources: v1.ResourceRequirements{
+								Requests: buildResourceList("1000m", "1G"),
+							},
+						},
+						{
+							Resources: v1.ResourceRequirements{
+								Requests: buildResourceList("2000m", "1G"),
+							},
+						},
+					},
+				},
+			},
+			expectedResource: NewResource(buildResourceList("3000m", "5G")),
+		},
+	}
+
+	for i, test := range tests {
+		req := getResourceRequest(test.pod)
+		if !reflect.DeepEqual(req, test.expectedResource) {
+			t.Errorf("case %d(%s) failed: \n expected %v, \n got: %v \n",
+				i, test.name, test.expectedResource, req)
+		}
+	}
+}

pkg/scheduler/api/resource_info.go

@@ -109,6 +109,23 @@ func (r *Resource) Sub(rr *Resource) *Resource {
 		r, rr))
 }
 
+// SetMaxResource compares with ResourceList and takes max value for each Resource.
+func (r *Resource) SetMaxResource(rr *Resource) {
+	if r == nil {
+		return
+	}
+
+	if rr.MilliCPU > r.MilliCPU {
+		r.MilliCPU = rr.MilliCPU
+	}
+	if rr.Memory > r.Memory {
+		r.Memory = rr.Memory
+	}
+	if rr.MilliGPU > r.MilliGPU {
+		r.MilliGPU = rr.MilliGPU
+	}
+}
+
 //Computes the delta between a resource oject representing available
 //resources an operand representing resources being requested.  Any
 //field that is less than 0 after the operation represents an