kubernetes/pkg/controller/podautoscaler/replica_calculator_test.go
Solly Ross 7846827fc0 Convert HPA controller to use autoscaling/v2alpha1
This commit converts the HPA controller over to using the new version of
the HorizontalPodAutoscaler object found in autoscaling/v2alpha1.  Note
that while the autoscaler will accept requests for object metrics, the
scale client will return an error on attempts to get object metrics
(since that requires the new custom metrics API, which is not yet
implemented).

This also enables the HPA object in v2alpha1 as a retrievable API
version by default.
2017-02-16 15:03:14 -05:00

689 lines
21 KiB
Go

/*
Copyright 2016 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package podautoscaler
import (
"encoding/json"
"fmt"
"math"
"strconv"
"strings"
"testing"
"time"
"k8s.io/apimachinery/pkg/api/resource"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/runtime"
restclient "k8s.io/client-go/rest"
core "k8s.io/client-go/testing"
"k8s.io/kubernetes/pkg/api/unversioned"
"k8s.io/kubernetes/pkg/api/v1"
"k8s.io/kubernetes/pkg/client/clientset_generated/clientset/fake"
"k8s.io/kubernetes/pkg/controller/podautoscaler/metrics"
heapster "k8s.io/heapster/metrics/api/v1/types"
metricsapi "k8s.io/heapster/metrics/apis/metrics/v1alpha1"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
type resourceInfo struct {
name v1.ResourceName
requests []resource.Quantity
levels []int64
// only applies to pod names returned from "heapster"
podNames []string
targetUtilization int32
expectedUtilization int32
expectedValue int64
}
type metricInfo struct {
name string
levels []float64
targetUtilization int64
expectedUtilization int64
}
type replicaCalcTestCase struct {
currentReplicas int32
expectedReplicas int32
expectedError error
timestamp time.Time
resource *resourceInfo
metric *metricInfo
podReadiness []v1.ConditionStatus
}
const (
testNamespace = "test-namespace"
podNamePrefix = "test-pod"
numContainersPerPod = 2
)
func (tc *replicaCalcTestCase) prepareTestClient(t *testing.T) *fake.Clientset {
fakeClient := &fake.Clientset{}
fakeClient.AddReactor("list", "pods", func(action core.Action) (handled bool, ret runtime.Object, err error) {
obj := &v1.PodList{}
for i := 0; i < int(tc.currentReplicas); i++ {
podReadiness := v1.ConditionTrue
if tc.podReadiness != nil {
podReadiness = tc.podReadiness[i]
}
podName := fmt.Sprintf("%s-%d", podNamePrefix, i)
pod := v1.Pod{
Status: v1.PodStatus{
Phase: v1.PodRunning,
Conditions: []v1.PodCondition{
{
Type: v1.PodReady,
Status: podReadiness,
},
},
},
ObjectMeta: metav1.ObjectMeta{
Name: podName,
Namespace: testNamespace,
Labels: map[string]string{
"name": podNamePrefix,
},
},
Spec: v1.PodSpec{
Containers: []v1.Container{{}, {}},
},
}
if tc.resource != nil && i < len(tc.resource.requests) {
pod.Spec.Containers[0].Resources = v1.ResourceRequirements{
Requests: v1.ResourceList{
tc.resource.name: tc.resource.requests[i],
},
}
pod.Spec.Containers[1].Resources = v1.ResourceRequirements{
Requests: v1.ResourceList{
tc.resource.name: tc.resource.requests[i],
},
}
}
obj.Items = append(obj.Items, pod)
}
return true, obj, nil
})
fakeClient.AddProxyReactor("services", func(action core.Action) (handled bool, ret restclient.ResponseWrapper, err error) {
var heapsterRawMemResponse []byte
if tc.resource != nil {
metrics := metricsapi.PodMetricsList{}
for i, resValue := range tc.resource.levels {
podName := fmt.Sprintf("%s-%d", podNamePrefix, i)
if len(tc.resource.podNames) > i {
podName = tc.resource.podNames[i]
}
podMetric := metricsapi.PodMetrics{
ObjectMeta: v1.ObjectMeta{
Name: podName,
Namespace: testNamespace,
},
Timestamp: unversioned.Time{Time: tc.timestamp},
Containers: make([]metricsapi.ContainerMetrics, numContainersPerPod),
}
for i := 0; i < numContainersPerPod; i++ {
podMetric.Containers[i] = metricsapi.ContainerMetrics{
Name: fmt.Sprintf("container%v", i),
Usage: v1.ResourceList{
v1.ResourceName(tc.resource.name): *resource.NewMilliQuantity(
int64(resValue),
resource.DecimalSI),
},
}
}
metrics.Items = append(metrics.Items, podMetric)
}
heapsterRawMemResponse, _ = json.Marshal(&metrics)
} else {
// only return the pods that we actually asked for
proxyAction := action.(core.ProxyGetAction)
pathParts := strings.Split(proxyAction.GetPath(), "/")
// pathParts should look like [ api, v1, model, namespaces, $NS, pod-list, $PODS, metrics, $METRIC... ]
if len(pathParts) < 9 {
return true, nil, fmt.Errorf("invalid heapster path %q", proxyAction.GetPath())
}
podNames := strings.Split(pathParts[7], ",")
podPresent := make([]bool, len(tc.metric.levels))
for _, name := range podNames {
if len(name) <= len(podNamePrefix)+1 {
return true, nil, fmt.Errorf("unknown pod %q", name)
}
num, err := strconv.Atoi(name[len(podNamePrefix)+1:])
if err != nil {
return true, nil, fmt.Errorf("unknown pod %q", name)
}
podPresent[num] = true
}
timestamp := tc.timestamp
metrics := heapster.MetricResultList{}
for i, level := range tc.metric.levels {
if !podPresent[i] {
continue
}
metric := heapster.MetricResult{
Metrics: []heapster.MetricPoint{{Timestamp: timestamp, Value: uint64(level), FloatValue: &tc.metric.levels[i]}},
LatestTimestamp: timestamp,
}
metrics.Items = append(metrics.Items, metric)
}
heapsterRawMemResponse, _ = json.Marshal(&metrics)
}
return true, newFakeResponseWrapper(heapsterRawMemResponse), nil
})
return fakeClient
}
func (tc *replicaCalcTestCase) runTest(t *testing.T) {
testClient := tc.prepareTestClient(t)
metricsClient := metrics.NewHeapsterMetricsClient(testClient, metrics.DefaultHeapsterNamespace, metrics.DefaultHeapsterScheme, metrics.DefaultHeapsterService, metrics.DefaultHeapsterPort)
replicaCalc := &ReplicaCalculator{
metricsClient: metricsClient,
podsGetter: testClient.Core(),
}
selector, err := metav1.LabelSelectorAsSelector(&metav1.LabelSelector{
MatchLabels: map[string]string{"name": podNamePrefix},
})
if err != nil {
require.Nil(t, err, "something went horribly wrong...")
}
if tc.resource != nil {
outReplicas, outUtilization, outRawValue, outTimestamp, err := replicaCalc.GetResourceReplicas(tc.currentReplicas, tc.resource.targetUtilization, tc.resource.name, testNamespace, selector)
if tc.expectedError != nil {
require.Error(t, err, "there should be an error calculating the replica count")
assert.Contains(t, err.Error(), tc.expectedError.Error(), "the error message should have contained the expected error message")
return
}
require.NoError(t, err, "there should not have been an error calculating the replica count")
assert.Equal(t, tc.expectedReplicas, outReplicas, "replicas should be as expected")
assert.Equal(t, tc.resource.expectedUtilization, outUtilization, "utilization should be as expected")
assert.Equal(t, tc.resource.expectedValue, outRawValue, "raw value should be as expected")
assert.True(t, tc.timestamp.Equal(outTimestamp), "timestamp should be as expected")
} else {
outReplicas, outUtilization, outTimestamp, err := replicaCalc.GetMetricReplicas(tc.currentReplicas, tc.metric.targetUtilization, tc.metric.name, testNamespace, selector)
if tc.expectedError != nil {
require.Error(t, err, "there should be an error calculating the replica count")
assert.Contains(t, err.Error(), tc.expectedError.Error(), "the error message should have contained the expected error message")
return
}
require.NoError(t, err, "there should not have been an error calculating the replica count")
assert.Equal(t, tc.expectedReplicas, outReplicas, "replicas should be as expected")
assert.Equal(t, tc.metric.expectedUtilization, outUtilization, "utilization should be as expected")
assert.True(t, tc.timestamp.Equal(outTimestamp), "timestamp should be as expected")
}
}
func TestReplicaCalcDisjointResourcesMetrics(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 1,
expectedError: fmt.Errorf("no metrics returned matched known pods"),
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0")},
levels: []int64{100},
podNames: []string{"an-older-pod-name"},
targetUtilization: 100,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleUp(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 5,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{300, 500, 700},
targetUtilization: 30,
expectedUtilization: 50,
expectedValue: numContainersPerPod * 500,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleUpUnreadyLessScale(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 4,
podReadiness: []v1.ConditionStatus{v1.ConditionFalse, v1.ConditionTrue, v1.ConditionTrue},
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{300, 500, 700},
targetUtilization: 30,
expectedUtilization: 60,
expectedValue: numContainersPerPod * 600,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleUpUnreadyNoScale(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 3,
podReadiness: []v1.ConditionStatus{v1.ConditionTrue, v1.ConditionFalse, v1.ConditionFalse},
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{400, 500, 700},
targetUtilization: 30,
expectedUtilization: 40,
expectedValue: numContainersPerPod * 400,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleUpCM(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 4,
metric: &metricInfo{
name: "qps",
levels: []float64{20.0, 10.0, 30.0},
targetUtilization: 15000,
expectedUtilization: 20000,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleUpCMUnreadyLessScale(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 4,
podReadiness: []v1.ConditionStatus{v1.ConditionTrue, v1.ConditionTrue, v1.ConditionFalse},
metric: &metricInfo{
name: "qps",
levels: []float64{50.0, 10.0, 30.0},
targetUtilization: 15000,
expectedUtilization: 30000,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleUpCMUnreadyNoScaleWouldScaleDown(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 3,
podReadiness: []v1.ConditionStatus{v1.ConditionFalse, v1.ConditionTrue, v1.ConditionFalse},
metric: &metricInfo{
name: "qps",
levels: []float64{50.0, 15.0, 30.0},
targetUtilization: 15000,
expectedUtilization: 15000,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleDown(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 5,
expectedReplicas: 3,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{100, 300, 500, 250, 250},
targetUtilization: 50,
expectedUtilization: 28,
expectedValue: numContainersPerPod * 280,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleDownCM(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 5,
expectedReplicas: 3,
metric: &metricInfo{
name: "qps",
levels: []float64{12.0, 12.0, 12.0, 12.0, 12.0},
targetUtilization: 20000,
expectedUtilization: 12000,
},
}
tc.runTest(t)
}
func TestReplicaCalcScaleDownIgnoresUnreadyPods(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 5,
expectedReplicas: 2,
podReadiness: []v1.ConditionStatus{v1.ConditionTrue, v1.ConditionTrue, v1.ConditionTrue, v1.ConditionFalse, v1.ConditionFalse},
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{100, 300, 500, 250, 250},
targetUtilization: 50,
expectedUtilization: 30,
expectedValue: numContainersPerPod * 300,
},
}
tc.runTest(t)
}
func TestReplicaCalcTolerance(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 3,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("0.9"), resource.MustParse("1.0"), resource.MustParse("1.1")},
levels: []int64{1010, 1030, 1020},
targetUtilization: 100,
expectedUtilization: 102,
expectedValue: numContainersPerPod * 1020,
},
}
tc.runTest(t)
}
func TestReplicaCalcToleranceCM(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 3,
metric: &metricInfo{
name: "qps",
levels: []float64{20.0, 21.0, 21.0},
targetUtilization: 20000,
expectedUtilization: 20666,
},
}
tc.runTest(t)
}
func TestReplicaCalcSuperfluousMetrics(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 4,
expectedReplicas: 24,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{4000, 9500, 3000, 7000, 3200, 2000},
targetUtilization: 100,
expectedUtilization: 587,
expectedValue: numContainersPerPod * 5875,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetrics(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 4,
expectedReplicas: 3,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{400, 95},
targetUtilization: 100,
expectedUtilization: 24,
expectedValue: 495, // numContainersPerPod * 247, for sufficiently large values of 247
},
}
tc.runTest(t)
}
func TestReplicaCalcEmptyMetrics(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 4,
expectedError: fmt.Errorf("unable to get metrics for resource cpu: no metrics returned from heapster"),
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{},
targetUtilization: 100,
},
}
tc.runTest(t)
}
func TestReplicaCalcEmptyCPURequest(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 1,
expectedError: fmt.Errorf("missing request for"),
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{},
levels: []int64{200},
targetUtilization: 100,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetricsNoChangeEq(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 2,
expectedReplicas: 2,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{1000},
targetUtilization: 100,
expectedUtilization: 100,
expectedValue: numContainersPerPod * 1000,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetricsNoChangeGt(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 2,
expectedReplicas: 2,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{1900},
targetUtilization: 100,
expectedUtilization: 190,
expectedValue: numContainersPerPod * 1900,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetricsNoChangeLt(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 2,
expectedReplicas: 2,
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{600},
targetUtilization: 100,
expectedUtilization: 60,
expectedValue: numContainersPerPod * 600,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetricsUnreadyNoChange(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 3,
podReadiness: []v1.ConditionStatus{v1.ConditionFalse, v1.ConditionTrue, v1.ConditionTrue},
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{100, 450},
targetUtilization: 50,
expectedUtilization: 45,
expectedValue: numContainersPerPod * 450,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetricsUnreadyScaleUp(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 3,
expectedReplicas: 4,
podReadiness: []v1.ConditionStatus{v1.ConditionFalse, v1.ConditionTrue, v1.ConditionTrue},
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{100, 2000},
targetUtilization: 50,
expectedUtilization: 200,
expectedValue: numContainersPerPod * 2000,
},
}
tc.runTest(t)
}
func TestReplicaCalcMissingMetricsUnreadyScaleDown(t *testing.T) {
tc := replicaCalcTestCase{
currentReplicas: 4,
expectedReplicas: 3,
podReadiness: []v1.ConditionStatus{v1.ConditionFalse, v1.ConditionTrue, v1.ConditionTrue, v1.ConditionTrue},
resource: &resourceInfo{
name: v1.ResourceCPU,
requests: []resource.Quantity{resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0"), resource.MustParse("1.0")},
levels: []int64{100, 100, 100},
targetUtilization: 50,
expectedUtilization: 10,
expectedValue: numContainersPerPod * 100,
},
}
tc.runTest(t)
}
// TestComputedToleranceAlgImplementation is a regression test which
// back-calculates a minimal percentage for downscaling based on a small percentage
// increase in pod utilization which is calibrated against the tolerance value.
func TestReplicaCalcComputedToleranceAlgImplementation(t *testing.T) {
startPods := int32(10)
// 150 mCPU per pod.
totalUsedCPUOfAllPods := int64(startPods * 150)
// Each pod starts out asking for 2X what is really needed.
// This means we will have a 50% ratio of used/requested
totalRequestedCPUOfAllPods := int32(2 * totalUsedCPUOfAllPods)
requestedToUsed := float64(totalRequestedCPUOfAllPods / int32(totalUsedCPUOfAllPods))
// Spread the amount we ask over 10 pods. We can add some jitter later in reportedLevels.
perPodRequested := totalRequestedCPUOfAllPods / startPods
// Force a minimal scaling event by satisfying (tolerance < 1 - resourcesUsedRatio).
target := math.Abs(1/(requestedToUsed*(1-tolerance))) + .01
finalCpuPercentTarget := int32(target * 100)
resourcesUsedRatio := float64(totalUsedCPUOfAllPods) / float64(float64(totalRequestedCPUOfAllPods)*target)
// i.e. .60 * 20 -> scaled down expectation.
finalPods := int32(math.Ceil(resourcesUsedRatio * float64(startPods)))
// To breach tolerance we will create a utilization ratio difference of tolerance to usageRatioToleranceValue)
tc := replicaCalcTestCase{
currentReplicas: startPods,
expectedReplicas: finalPods,
resource: &resourceInfo{
name: v1.ResourceCPU,
levels: []int64{
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
totalUsedCPUOfAllPods / 10,
},
requests: []resource.Quantity{
resource.MustParse(fmt.Sprint(perPodRequested+100) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested-100) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested+10) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested-10) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested+2) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested-2) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested+1) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested-1) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested) + "m"),
resource.MustParse(fmt.Sprint(perPodRequested) + "m"),
},
targetUtilization: finalCpuPercentTarget,
expectedUtilization: int32(totalUsedCPUOfAllPods*100) / totalRequestedCPUOfAllPods,
expectedValue: numContainersPerPod * totalUsedCPUOfAllPods / 10,
},
}
tc.runTest(t)
// Reuse the data structure above, now testing "unscaling".
// Now, we test that no scaling happens if we are in a very close margin to the tolerance
target = math.Abs(1/(requestedToUsed*(1-tolerance))) + .004
finalCpuPercentTarget = int32(target * 100)
tc.resource.targetUtilization = finalCpuPercentTarget
tc.currentReplicas = startPods
tc.expectedReplicas = startPods
tc.runTest(t)
}
// TODO: add more tests