[cherry-pick 0.10.x] leave max container request values at original index

pkg/pod/pod.go

@@ -119,7 +119,7 @@ func MakePod(images pipeline.Images, taskRun *v1alpha1.TaskRun, taskSpec v1alpha
 	initContainers = append(initContainers, entrypointInit)
 	volumes = append(volumes, toolsVolume, downwardVolume)
 
-	// Zero out non-max resource requests, move max resource requests to the last step.
+	// Zero out non-max resource requests.
 	stepContainers = resolveResourceRequests(stepContainers)
 
 	// Add implicit env vars.

pkg/pod/pod_test.go

@@ -436,10 +436,16 @@ func TestMakePod(t *testing.T) {
 					"cmd",
 					"--",
 				},
-				Env:                    implicitEnvVars,
-				VolumeMounts:           append([]corev1.VolumeMount{toolsMount, downwardMount}, implicitVolumeMounts...),
-				WorkingDir:             pipeline.WorkspaceDir,
-				Resources:              corev1.ResourceRequirements{Requests: allZeroQty()},
+				Env:          implicitEnvVars,
+				VolumeMounts: append([]corev1.VolumeMount{toolsMount, downwardMount}, implicitVolumeMounts...),
+				WorkingDir:   pipeline.WorkspaceDir,
+				Resources: corev1.ResourceRequirements{
+					Requests: corev1.ResourceList{
+						corev1.ResourceCPU:              resource.MustParse("8"),
+						corev1.ResourceMemory:           zeroQty,
+						corev1.ResourceEphemeralStorage: zeroQty,
+					},
+				},
 				TerminationMessagePath: "/tekton/termination",
 			}, {
 				Name:    "step-unnamed-1",
@@ -461,7 +467,7 @@ func TestMakePod(t *testing.T) {
 				WorkingDir:   pipeline.WorkspaceDir,
 				Resources: corev1.ResourceRequirements{
 					Requests: corev1.ResourceList{
-						corev1.ResourceCPU:              resource.MustParse("8"),
+						corev1.ResourceCPU:              zeroQty,
 						corev1.ResourceMemory:           resource.MustParse("100Gi"),
 						corev1.ResourceEphemeralStorage: zeroQty,
 					},

pkg/pod/resource_request.go

@@ -33,20 +33,36 @@ func allZeroQty() corev1.ResourceList {
 
 func resolveResourceRequests(containers []corev1.Container) []corev1.Container {
 	max := allZeroQty()
-	for _, c := range containers {
+	resourceNames := []corev1.ResourceName{corev1.ResourceCPU, corev1.ResourceMemory, corev1.ResourceEphemeralStorage}
+	maxIndicesByResource := make(map[corev1.ResourceName]int, len(resourceNames))
+	for _, resourceName := range resourceNames {
+		maxIndicesByResource[resourceName] = -1
+	}
+
+	// Find max resource requests and associated list indices for
+	// containers for CPU, memory, and ephemeral storage resources
+	for i, c := range containers {
 		for k, v := range c.Resources.Requests {
 			if v.Cmp(max[k]) > 0 {
+				maxIndicesByResource[k] = i
 				max[k] = v
 			}
 		}
 	}
 
-	// Set resource requests for all steps but the last container to
-	// zero.
-	for i := range containers[:len(containers)-1] {
-		containers[i].Resources.Requests = allZeroQty()
+	// Set all non max resource requests to 0. Leave max request at index
+	// originally defined to account for limit of step.
+	for i := range containers {
+		if containers[i].Resources.Requests == nil {
+			containers[i].Resources.Requests = allZeroQty()
+			continue
+		}
+		for _, resourceName := range resourceNames {
+			if maxIndicesByResource[resourceName] != i {
+				containers[i].Resources.Requests[resourceName] = zeroQty
+			}
+		}
 	}
-	// Set the last container's request to the max of all resources.
-	containers[len(containers)-1].Resources.Requests = max
+
 	return containers
 }

pkg/pod/resource_request_test.go

@@ -70,18 +70,61 @@ func TestResolveResourceRequests(t *testing.T) {
 			},
 		}},
 		want: []corev1.Container{{
-			// All zeroed out.
-			Resources: corev1.ResourceRequirements{Requests: allZeroQty()},
+			// ResourceCPU max request
+			Resources: corev1.ResourceRequirements{
+				Requests: corev1.ResourceList{
+					corev1.ResourceCPU:              resource.MustParse("10"),
+					corev1.ResourceMemory:           zeroQty,
+					corev1.ResourceEphemeralStorage: zeroQty,
+				},
+			},
 		}, {
-			// Requests zeroed out, limits remain.
+			// ResourceMemory max request
 			Resources: corev1.ResourceRequirements{
-				Requests: allZeroQty(),
+				Requests: corev1.ResourceList{
+					corev1.ResourceCPU:              zeroQty,
+					corev1.ResourceMemory:           resource.MustParse("10Gi"),
+					corev1.ResourceEphemeralStorage: zeroQty,
+				},
+				Limits: corev1.ResourceList{
+					corev1.ResourceMemory: resource.MustParse("11Gi"),
+				},
+			},
+		}, {
+			// ResourceEphemeralStorage max request
+			Resources: corev1.ResourceRequirements{
+				Requests: corev1.ResourceList{
+					corev1.ResourceCPU:              zeroQty,
+					corev1.ResourceMemory:           zeroQty,
+					corev1.ResourceEphemeralStorage: resource.MustParse("100Gi"),
+				},
+				Limits: corev1.ResourceList{
+					corev1.ResourceMemory: resource.MustParse("100Gi"),
+				},
+			},
+		}},
+	}, {
+		desc: "Max requests all with step2",
+		in: []corev1.Container{{
+			Resources: corev1.ResourceRequirements{
+				Requests: corev1.ResourceList{
+					corev1.ResourceCPU:              resource.MustParse("10"),
+					corev1.ResourceMemory:           resource.MustParse("10Gi"),
+					corev1.ResourceEphemeralStorage: resource.MustParse("100Gi"),
+				},
+			},
+		}, {
+			Resources: corev1.ResourceRequirements{
+				Requests: corev1.ResourceList{
+					corev1.ResourceCPU:              resource.MustParse("11"),
+					corev1.ResourceMemory:           resource.MustParse("11Gi"),
+					corev1.ResourceEphemeralStorage: resource.MustParse("101Gi"),
+				},
 				Limits: corev1.ResourceList{
 					corev1.ResourceMemory: resource.MustParse("11Gi"),
 				},
 			},
 		}, {
-			// Requests to the max, limits remain.
 			Resources: corev1.ResourceRequirements{
 				Requests: corev1.ResourceList{
 					corev1.ResourceCPU:              resource.MustParse("10"),
@@ -93,7 +136,75 @@ func TestResolveResourceRequests(t *testing.T) {
 				},
 			},
 		}},
-	}} {
+		want: []corev1.Container{{
+			// All zeroed out since step 2 has max requests
+			Resources: corev1.ResourceRequirements{
+				Requests: allZeroQty(),
+			},
+		}, {
+			// All max requests
+			Resources: corev1.ResourceRequirements{
+				Requests: corev1.ResourceList{
+					corev1.ResourceCPU:              resource.MustParse("11"),
+					corev1.ResourceMemory:           resource.MustParse("11Gi"),
+					corev1.ResourceEphemeralStorage: resource.MustParse("101Gi"),
+				},
+				Limits: corev1.ResourceList{
+					corev1.ResourceMemory: resource.MustParse("11Gi"),
+				},
+			},
+		}, {
+			// All zeroed out since step 2 has max requests
+			Resources: corev1.ResourceRequirements{
+				Requests: allZeroQty(),
+				Limits: corev1.ResourceList{
+					corev1.ResourceMemory: resource.MustParse("100Gi"),
+				},
+			},
+		}},
+	},
+		{
+			desc: "Only one step container with only memory request value filled out",
+			in: []corev1.Container{{
+				Resources: corev1.ResourceRequirements{
+					Requests: corev1.ResourceList{
+						corev1.ResourceMemory: resource.MustParse("10Gi"),
+					},
+				},
+			}},
+			want: []corev1.Container{{
+				// ResourceMemory max request set. zeroQty for non set resources.
+				Resources: corev1.ResourceRequirements{
+					Requests: corev1.ResourceList{
+						corev1.ResourceCPU:              zeroQty,
+						corev1.ResourceMemory:           resource.MustParse("10Gi"),
+						corev1.ResourceEphemeralStorage: zeroQty,
+					},
+				},
+			}},
+		}, {
+			desc: "Only one step container with all request values filled out",
+			in: []corev1.Container{{
+				Resources: corev1.ResourceRequirements{
+					Requests: corev1.ResourceList{
+						corev1.ResourceCPU:              resource.MustParse("10"),
+						corev1.ResourceMemory:           resource.MustParse("10Gi"),
+						corev1.ResourceEphemeralStorage: resource.MustParse("100Gi"),
+					},
+				},
+			}},
+			want: []corev1.Container{{
+				// All max values set
+				Resources: corev1.ResourceRequirements{
+					Requests: corev1.ResourceList{
+						corev1.ResourceCPU:              resource.MustParse("10"),
+						corev1.ResourceMemory:           resource.MustParse("10Gi"),
+						corev1.ResourceEphemeralStorage: resource.MustParse("100Gi"),
+					},
+				},
+			}},
+		},
+	} {
 		t.Run(c.desc, func(t *testing.T) {
 			got := resolveResourceRequests(c.in)
 			if d := cmp.Diff(c.want, got, resourceQuantityCmp); d != "" {