From 500aaea4ddbd5dd0df14f1dd466fffde2c1ffba1 Mon Sep 17 00:00:00 2001
From: Jan Chaloupka <jchaloup@redhat.com>
Date: Thu, 11 Feb 2021 15:57:24 +0100
Subject: [PATCH] LowNodeUtilization: unit test resourceUsagePercentages to
 validate percentages are computed correctly

---
 .../strategies/lownodeutilization_test.go     | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/pkg/descheduler/strategies/lownodeutilization_test.go b/pkg/descheduler/strategies/lownodeutilization_test.go
index 851afcc0b..01ea264a1 100644
--- a/pkg/descheduler/strategies/lownodeutilization_test.go
+++ b/pkg/descheduler/strategies/lownodeutilization_test.go
@@ -19,6 +19,7 @@ package strategies
 import (
 	"context"
 	"fmt"
+	"math"
 	"strings"
 	"testing"
 
@@ -776,3 +777,41 @@ func TestWithTaints(t *testing.T) {
 		})
 	}
 }
+
+func TestResourceUsagePercentages(t *testing.T) {
+	resourceUsagePercentage := resourceUsagePercentages(NodeUsage{
+		node: &v1.Node{
+			Status: v1.NodeStatus{
+				Capacity: v1.ResourceList{
+					v1.ResourceCPU:    *resource.NewMilliQuantity(2000, resource.DecimalSI),
+					v1.ResourceMemory: *resource.NewQuantity(3977868*1024, resource.BinarySI),
+					v1.ResourcePods:   *resource.NewQuantity(29, resource.BinarySI),
+				},
+				Allocatable: v1.ResourceList{
+					v1.ResourceCPU:    *resource.NewMilliQuantity(1930, resource.DecimalSI),
+					v1.ResourceMemory: *resource.NewQuantity(3287692*1024, resource.BinarySI),
+					v1.ResourcePods:   *resource.NewQuantity(29, resource.BinarySI),
+				},
+			},
+		},
+		usage: map[v1.ResourceName]*resource.Quantity{
+			v1.ResourceCPU:    resource.NewMilliQuantity(1220, resource.DecimalSI),
+			v1.ResourceMemory: resource.NewQuantity(3038982964, resource.BinarySI),
+			v1.ResourcePods:   resource.NewQuantity(11, resource.BinarySI),
+		},
+	})
+
+	expectedUsageInIntPercentage := map[v1.ResourceName]float64{
+		v1.ResourceCPU:    63,
+		v1.ResourceMemory: 90,
+		v1.ResourcePods:   37,
+	}
+
+	for resourceName, percentage := range expectedUsageInIntPercentage {
+		if math.Floor(resourceUsagePercentage[resourceName]) != percentage {
+			t.Errorf("Incorrect percentange computation, expected %v, got math.Floor(%v) instead", percentage, resourceUsagePercentage[resourceName])
+		}
+	}
+
+	t.Logf("resourceUsagePercentage: %#v\n", resourceUsagePercentage)
+}