From 19c91a59ab709eee4ff7a6beb923c2576e8c420f Mon Sep 17 00:00:00 2001
From: Ted Yu <yuzhihong@gmail.com>
Date: Mon, 3 Jun 2019 13:16:08 -0700
Subject: [PATCH] Iterate through thresholds in managerImpl#synchronize

---
 pkg/kubelet/eviction/eviction_manager.go |  6 +--
 pkg/kubelet/eviction/helpers.go          | 11 +++++
 pkg/kubelet/eviction/helpers_test.go     | 59 ++++++++++++++++++++++++
 3 files changed, 72 insertions(+), 4 deletions(-)

diff --git a/pkg/kubelet/eviction/eviction_manager.go b/pkg/kubelet/eviction/eviction_manager.go
index a1ab99869ab..a471383d7ff 100644
--- a/pkg/kubelet/eviction/eviction_manager.go
+++ b/pkg/kubelet/eviction/eviction_manager.go
@@ -324,10 +324,8 @@ func (m *managerImpl) synchronize(diskInfoProvider DiskInfoProvider, podFunc Act
 
 	// rank the thresholds by eviction priority
 	sort.Sort(byEvictionPriority(thresholds))
-	thresholdToReclaim := thresholds[0]
-	resourceToReclaim, found := signalToResource[thresholdToReclaim.Signal]
-	if !found {
-		klog.V(3).Infof("eviction manager: threshold %s was crossed, but reclaim is not implemented for this threshold.", thresholdToReclaim.Signal)
+	thresholdToReclaim, resourceToReclaim, foundAny := getReclaimableThreshold(thresholds)
+	if !foundAny {
 		return nil
 	}
 	klog.Warningf("eviction manager: attempting to reclaim %v", resourceToReclaim)
diff --git a/pkg/kubelet/eviction/helpers.go b/pkg/kubelet/eviction/helpers.go
index 50279fd1977..01152eac705 100644
--- a/pkg/kubelet/eviction/helpers.go
+++ b/pkg/kubelet/eviction/helpers.go
@@ -98,6 +98,17 @@ func validSignal(signal evictionapi.Signal) bool {
 	return found
 }
 
+// getReclaimableThreshold finds the threshold and resource to reclaim
+func getReclaimableThreshold(thresholds []evictionapi.Threshold) (evictionapi.Threshold, v1.ResourceName, bool) {
+	for _, thresholdToReclaim := range thresholds {
+		if resourceToReclaim, ok := signalToResource[thresholdToReclaim.Signal]; ok {
+			return thresholdToReclaim, resourceToReclaim, true
+		}
+		klog.V(3).Infof("eviction manager: threshold %s was crossed, but reclaim is not implemented for this threshold.", thresholdToReclaim.Signal)
+	}
+	return evictionapi.Threshold{}, "", false
+}
+
 // ParseThresholdConfig parses the flags for thresholds.
 func ParseThresholdConfig(allocatableConfig []string, evictionHard, evictionSoft, evictionSoftGracePeriod, evictionMinimumReclaim map[string]string) ([]evictionapi.Threshold, error) {
 	results := []evictionapi.Threshold{}
diff --git a/pkg/kubelet/eviction/helpers_test.go b/pkg/kubelet/eviction/helpers_test.go
index c10a4e6e23e..81a3c451cd6 100644
--- a/pkg/kubelet/eviction/helpers_test.go
+++ b/pkg/kubelet/eviction/helpers_test.go
@@ -40,6 +40,65 @@ func quantityMustParse(value string) *resource.Quantity {
 	return &q
 }
 
+func TestGetReclaimableThreshold(t *testing.T) {
+	testCases := map[string]struct {
+		thresholds []evictionapi.Threshold
+	}{
+		"": {
+			thresholds: []evictionapi.Threshold{
+				{
+					Signal:   evictionapi.SignalAllocatableMemoryAvailable,
+					Operator: evictionapi.OpLessThan,
+					Value: evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("150Mi"),
+					},
+					MinReclaim: &evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("0"),
+					},
+				},
+				{
+					Signal:   evictionapi.SignalMemoryAvailable,
+					Operator: evictionapi.OpLessThan,
+					Value: evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("150Mi"),
+					},
+					MinReclaim: &evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("0"),
+					},
+				},
+				{
+					Signal:   evictionapi.SignalImageFsAvailable,
+					Operator: evictionapi.OpLessThan,
+					Value: evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("150Mi"),
+					},
+					MinReclaim: &evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("2Gi"),
+					},
+				},
+				{
+					Signal:   evictionapi.SignalNodeFsAvailable,
+					Operator: evictionapi.OpLessThan,
+					Value: evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("100Mi"),
+					},
+					MinReclaim: &evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("1Gi"),
+					},
+				},
+			},
+		},
+	}
+	for testName, testCase := range testCases {
+		sort.Sort(byEvictionPriority(testCase.thresholds))
+		_, resource, ok := getReclaimableThreshold(testCase.thresholds)
+		print(resource)
+		if !ok {
+			t.Errorf("Didn't find reclaimable threshold, test: %v", testName)
+		}
+	}
+}
+
 func TestParseThresholdConfig(t *testing.T) {
 	gracePeriod, _ := time.ParseDuration("30s")
 	testCases := map[string]struct {