kubelet: eviction: allow minimum reclaim as percentage

pkg/kubelet/eviction/eviction_manager_test.go

@@ -613,7 +613,9 @@ func TestMinReclaim(t *testing.T) {
 				Value: ThresholdValue{
 					Quantity: quantityMustParse("1Gi"),
 				},
-				MinReclaim: quantityMustParse("500Mi"),
+				MinReclaim: &ThresholdValue{
+					Quantity: quantityMustParse("500Mi"),
+				},
 			},
 		},
 	}
@@ -788,7 +790,9 @@ func TestNodeReclaimFuncs(t *testing.T) {
 				Value: ThresholdValue{
 					Quantity: quantityMustParse("1Gi"),
 				},
-				MinReclaim: quantityMustParse("500Mi"),
+				MinReclaim: &ThresholdValue{
+					Quantity: quantityMustParse("500Mi"),
+				},
 			},
 		},
 	}

pkg/kubelet/eviction/helpers.go

@@ -256,21 +256,40 @@ func parseGracePeriods(expr string) (map[Signal]time.Duration, error) {
 }
 
 // parseMinimumReclaims parses the minimum reclaim statements
-func parseMinimumReclaims(expr string) (map[Signal]resource.Quantity, error) {
+func parseMinimumReclaims(expr string) (map[Signal]ThresholdValue, error) {
 	if len(expr) == 0 {
 		return nil, nil
 	}
-	results := map[Signal]resource.Quantity{}
+	results := map[Signal]ThresholdValue{}
 	statements := strings.Split(expr, ",")
 	for _, statement := range statements {
 		parts := strings.Split(statement, "=")
 		if len(parts) != 2 {
-			return nil, fmt.Errorf("invalid eviction minimum reclaim syntax: %v, expected <signal>=<quantity>", statement)
+			return nil, fmt.Errorf("invalid eviction minimum reclaim syntax: %v, expected <signal>=<value>", statement)
 		}
 		signal := Signal(parts[0])
 		if !validSignal(signal) {
 			return nil, fmt.Errorf(unsupportedEvictionSignal, signal)
 		}
+
+		quantityValue := parts[1]
+		if strings.HasSuffix(quantityValue, "%") {
+			percentage, err := parsePercentage(quantityValue)
+			if err != nil {
+				return nil, err
+			}
+			if percentage <= 0 {
+				return nil, fmt.Errorf("eviction percentage minimum reclaim %v must be positive: %s", signal, quantityValue)
+			}
+			// check against duplicate statements
+			if _, found := results[signal]; found {
+				return nil, fmt.Errorf("duplicate eviction minimum reclaim specified for %v", signal)
+			}
+			results[signal] = ThresholdValue{
+				Percentage: percentage,
+			}
+			continue
+		}
 		// check against duplicate statements
 		if _, found := results[signal]; found {
 			return nil, fmt.Errorf("duplicate eviction minimum reclaim specified for %v", signal)
@@ -282,7 +301,9 @@ func parseMinimumReclaims(expr string) (map[Signal]resource.Quantity, error) {
 		if err != nil {
 			return nil, err
 		}
-		results[signal] = quantity
+		results[signal] = ThresholdValue{
+			Quantity: &quantity,
+		}
 	}
 	return results, nil
 }
@@ -650,7 +671,7 @@ func thresholdsMet(thresholds []Threshold, observations signalObservations, enfo
 		quantity := getThresholdQuantity(threshold.Value, observed.capacity)
 		// if enforceMinReclaim is specified, we compare relative to value - minreclaim
 		if enforceMinReclaim && threshold.MinReclaim != nil {
-			quantity.Add(*threshold.MinReclaim)
+			quantity.Add(*getThresholdQuantity(*threshold.MinReclaim, observed.capacity))
 		}
 		thresholdResult := quantity.Cmp(*observed.available)
 		switch threshold.Operator {